diff --git a/docs/guide/migrate-from-unbuild.md b/docs/guide/migrate-from-unbuild.md
new file mode 100644
index 000000000..64e4cdd6c
--- /dev/null
+++ b/docs/guide/migrate-from-unbuild.md
@@ -0,0 +1,47 @@
+# Migrate from unbuild
+
+[unbuild](https://github.com/unjs/unbuild) is a popular unified JavaScript build system from the unjs ecosystem. If you're currently using `unbuild` and want to migrate to `tsdown`, the process is straightforward thanks to the dedicated `migrate` command with the `--from unbuild` option:
+
+```bash
+npx tsdown migrate --from unbuild
+```
+
+> [!WARNING]
+> Please save your changes before migration. The migration process may modify your configuration files, so it's important to ensure all your changes are committed or backed up beforehand.
+
+## What Gets Migrated
+
+The migration process handles:
+
+1. **Package.json** changes:
+   - Dependencies: Updates `unbuild` dependencies to `tsdown`
+   - Scripts: Updates any scripts using `unbuild` to use `tsdown` instead
+   - Configuration: Migrates any `unbuild` configuration in package.json to `tsdown` format
+
+2. **Config Files**:
+   - Converts `build.config.*` files to `tsdown.config.*` files
+   - Updates imports from `unbuild` to `tsdown`
+   - Transforms `defineBuildConfig` to `defineConfig`
+   - Adapts build configuration options to match tsdown equivalents
+
+## Migration Options
+
+The `migrate` command supports the following options to customize the migration process:
+
+- `--cwd <dir>` (or `-c`): Specify the working directory for the migration.
+- `--dry-run` (or `-d`): Perform a dry run to preview the migration without making any changes.
+- `--from <source>`: Specify the source bundler to migrate from (defaults to `tsup`, use `unbuild` for unbuild migration).
+
+With these options, you can easily tailor the migration process to fit your specific project setup.
+
+## Differences from unbuild
+
+While `tsdown` aims to provide a smooth migration experience from `unbuild`, there are some notable differences to be aware of:
+
+1. **Configuration Format**: tsdown uses a slightly different configuration format. The migration script handles most common options, but you may need to manually adjust some advanced configurations.
+
+2. **Builders**: unbuild's `mkdist` builder is mapped to tsdown's `dts` builder, but there might be slight differences in behavior.
+
+3. **Rollup vs Rolldown**: unbuild uses Rollup, whereas tsdown uses [Rolldown](https://rolldown.rs/), a Rust-based bundler that's faster and more efficient.
+
+After migration, it's recommended to review your configuration and build output to ensure everything is working as expected.
diff --git a/src/cli.ts b/src/cli.ts
index 72914817a..75a5e26c8 100644
--- a/src/cli.ts
+++ b/src/cli.ts
@@ -51,10 +51,13 @@ cli
   })
 
 cli
-  .command('migrate', 'Migrate from tsup to tsdown')
+  .command('migrate', 'Migrate from tsup or unbuild to tsdown')
   .option('-c, --cwd <dir>', 'Working directory')
   .option('-d, --dry-run', 'Dry run')
+  .option('--tsup', 'Migrate from tsup, default')
+  .option('--unbuild', 'Migrate from unbuild')
   .action(async (args) => {
+    args.from = args.unbuild ? 'unbuild' : 'tsup'
     const { migrate } = await import('./migrate')
     await migrate(args)
   })
diff --git a/src/migrate/index.ts b/src/migrate/index.ts
new file mode 100644
index 000000000..8ea6d3d2e
--- /dev/null
+++ b/src/migrate/index.ts
@@ -0,0 +1,57 @@
+import process from 'node:process'
+import { green, underline } from 'ansis'
+import consola from 'consola'
+import { migrateTsup } from './tsup'
+import { migrateUnbuild } from './unbuild'
+
+export async function migrate({
+  cwd,
+  dryRun,
+  from,
+}: {
+  cwd?: string
+  dryRun?: boolean
+  from?: 'tsup' | 'unbuild'
+}): Promise<void> {
+  if (dryRun) {
+    consola.info('Dry run enabled. No changes were made.')
+  } else {
+    const confirm = await consola.prompt(
+      `Before proceeding, review the migration guide at ${underline`https://tsdown.dev/guide/migrate-from-${from}`}, as this process will modify your files.\n` +
+        `Uncommitted changes will be lost. Use the ${green`--dry-run`} flag to preview changes without applying them.\n\n` +
+        'Continue?',
+      { type: 'confirm' },
+    )
+    if (!confirm) {
+      consola.error('Migration cancelled.')
+      process.exitCode = 1
+      return
+    }
+  }
+
+  if (cwd) process.chdir(cwd)
+
+  if (from === 'unbuild') {
+    return migrateUnbuild(dryRun)
+  }
+  // Default to tsup migration
+  return migrateTsup(dryRun)
+}
+
+// rename key but keep order
+export function renameKey(
+  obj: Record<string, any>,
+  oldKey: string,
+  newKey: string,
+  newValue?: any,
+): Record<string, any> {
+  const newObj: Record<string, any> = {}
+  for (const key of Object.keys(obj)) {
+    if (key === oldKey) {
+      newObj[newKey] = newValue || obj[oldKey]
+    } else {
+      newObj[key] = obj[key]
+    }
+  }
+  return newObj
+}
diff --git a/src/migrate.ts b/src/migrate/tsup.ts
similarity index 75%
rename from src/migrate.ts
rename to src/migrate/tsup.ts
index 3cb248eaa..c00e1a644 100644
--- a/src/migrate.ts
+++ b/src/migrate/tsup.ts
@@ -1,35 +1,11 @@
 import { existsSync } from 'node:fs'
 import { readFile, unlink, writeFile } from 'node:fs/promises'
 import process from 'node:process'
-import { green, underline } from 'ansis'
 import consola from 'consola'
-import { version } from '../package.json'
-
-export async function migrate({
-  cwd,
-  dryRun,
-}: {
-  cwd?: string
-  dryRun?: boolean
-}): Promise<void> {
-  if (dryRun) {
-    consola.info('Dry run enabled. No changes were made.')
-  } else {
-    const confirm = await consola.prompt(
-      `Before proceeding, review the migration guide at ${underline`https://tsdown.dev/guide/migrate-from-tsup`}, as this process will modify your files.\n` +
-        `Uncommitted changes will be lost. Use the ${green`--dry-run`} flag to preview changes without applying them.\n\n` +
-        'Continue?',
-      { type: 'confirm' },
-    )
-    if (!confirm) {
-      consola.error('Migration cancelled.')
-      process.exitCode = 1
-      return
-    }
-  }
-
-  if (cwd) process.chdir(cwd)
+import { version } from '../../package.json'
+import { renameKey } from '.'
 
+export async function migrateTsup(dryRun?: boolean): Promise<void> {
   let migrated = await migratePackageJson(dryRun)
   if (await migrateTsupConfig(dryRun)) {
     migrated = true
@@ -123,6 +99,7 @@ const TSUP_FILES = [
   'tsup.config.mjs',
   'tsup.config.json',
 ]
+
 async function migrateTsupConfig(dryRun?: boolean): Promise<boolean> {
   let found = false
 
@@ -156,21 +133,3 @@ async function migrateTsupConfig(dryRun?: boolean): Promise<boolean> {
 
   return found
 }
-
-// rename key but keep order
-function renameKey(
-  obj: Record<string, any>,
-  oldKey: string,
-  newKey: string,
-  newValue?: any,
-) {
-  const newObj: Record<string, any> = {}
-  for (const key of Object.keys(obj)) {
-    if (key === oldKey) {
-      newObj[newKey] = newValue || obj[oldKey]
-    } else {
-      newObj[key] = obj[key]
-    }
-  }
-  return newObj
-}
diff --git a/src/migrate/unbuild.ts b/src/migrate/unbuild.ts
new file mode 100644
index 000000000..deeced1cf
--- /dev/null
+++ b/src/migrate/unbuild.ts
@@ -0,0 +1,130 @@
+import { existsSync } from 'node:fs'
+import { readFile, unlink, writeFile } from 'node:fs/promises'
+import process from 'node:process'
+import consola from 'consola'
+import { version } from '../../package.json'
+import { renameKey } from '.'
+
+export async function migrateUnbuild(dryRun?: boolean): Promise<void> {
+  let migrated = await migratePackageJson(dryRun)
+  if (await migrateUnbuildConfig(dryRun)) {
+    migrated = true
+  }
+  if (migrated) {
+    consola.success(
+      'Migration completed. Remember to run install command with your package manager.',
+    )
+  } else {
+    consola.error('No migration performed.')
+    process.exitCode = 1
+  }
+}
+
+async function migratePackageJson(dryRun?: boolean): Promise<boolean> {
+  if (!existsSync('package.json')) {
+    consola.error('No package.json found')
+    return false
+  }
+
+  const pkgRaw = await readFile('package.json', 'utf-8')
+  let pkg = JSON.parse(pkgRaw)
+  const semver = `^${version}`
+  let found = false
+  if (pkg.dependencies?.unbuild) {
+    consola.info('Migrating `dependencies` to tsdown.')
+    found = true
+    pkg.dependencies = renameKey(pkg.dependencies, 'unbuild', 'tsdown', semver)
+  }
+  if (pkg.devDependencies?.unbuild) {
+    consola.info('Migrating `devDependencies` to tsdown.')
+    found = true
+    pkg.devDependencies = renameKey(
+      pkg.devDependencies,
+      'unbuild',
+      'tsdown',
+      semver,
+    )
+  }
+  if (pkg.peerDependencies?.unbuild) {
+    consola.info('Migrating `peerDependencies` to tsdown.')
+    found = true
+    pkg.peerDependencies = renameKey(
+      pkg.peerDependencies,
+      'unbuild',
+      'tsdown',
+      '*',
+    )
+  }
+  if (pkg.unbuild) {
+    consola.info('Migrating `unbuild` field in package.json to `tsdown`.')
+    found = true
+    pkg = renameKey(pkg, 'unbuild', 'tsdown')
+  }
+
+  if (!found) {
+    consola.warn('No unbuild-related fields found in package.json')
+    return false
+  }
+
+  const pkgStr = `${JSON.stringify(pkg, null, 2)}\n`
+  if (dryRun) {
+    const { createPatch } = await import('diff')
+    consola.info('[dry-run] package.json:')
+    console.info(createPatch('package.json', pkgRaw, pkgStr))
+  } else {
+    await writeFile('package.json', pkgStr)
+    consola.success('Migrated `package.json`')
+  }
+  return true
+}
+
+const UNBUILD_CONFIG_FILES = [
+  'build.config.ts',
+  'build.config.cts',
+  'build.config.mts',
+  'build.config.js',
+  'build.config.cjs',
+  'build.config.mjs',
+  'build.config.json',
+]
+
+async function migrateUnbuildConfig(dryRun?: boolean): Promise<boolean> {
+  let found = false
+
+  for (const file of UNBUILD_CONFIG_FILES) {
+    if (!existsSync(file)) continue
+    consola.info(`Found \`${file}\``)
+    found = true
+
+    const unbuildConfigRaw = await readFile(file, 'utf-8')
+
+    let tsdownConfig = unbuildConfigRaw
+      .replaceAll(/\bunbuild\b/g, 'tsdown')
+      .replaceAll(/\bdefineBuildConfig\b/g, 'defineConfig')
+
+    // Replace unbuild specific options with tsdown equivalents
+    // This is a simplified approach - might need to be expanded based on actual options mapping
+    tsdownConfig = tsdownConfig
+      .replaceAll(/builder:\s*["']mkdist["']/g, 'builder: "dts"')
+      .replaceAll('rollup:', 'rolldown:')
+
+    const renamed = file.replace('build', 'tsdown')
+    if (dryRun) {
+      const { createTwoFilesPatch } = await import('diff')
+      consola.info(`[dry-run] ${file} -> ${renamed}:`)
+      console.info(
+        createTwoFilesPatch(file, renamed, unbuildConfigRaw, tsdownConfig),
+      )
+    } else {
+      await writeFile(renamed, tsdownConfig, 'utf8')
+      await unlink(file)
+      consola.success(`Migrated \`${file}\` to \`${renamed}\``)
+    }
+  }
+
+  if (!found) {
+    consola.warn('No unbuild config found')
+  }
+
+  return found
+}