A cradle apparatus includes a built-in scanning module, and is used for mounting a portable electronic device. The cradle apparatus includes a housing and a scanning module. The housing has an accommodating slot with a connector therein and a transparent scanning region on the bottom thereof, below which the scanning module is placed. When a portable electronic device is connected to the connector of the cradle apparatus, the portable electronic device can control the scanning module to scan a document placed atop the transparent scanning region.