The invention discloses a circuit for scanning codes. The circuit comprises a trigger circuit, a scanning circuit, a control circuit, a Bluetooth circuit, a liquid crystal display circuit, a USB interface circuit and a status indicate circuit, wherein the trigger circuit drives the scanning circuit to work based on the trigger signal and drives the control circuit to send a locking signal, the scanning circuit sends the scanned data information to the control circuit, the control circuit stores the received data information, the Bluetooth circuit saves the data information sent by the controlcircuit to a terminal device through the Bluetooth transmission, the liquid crystal display circuit displays the data information of a target bar code obtained by the scanning circuit, the USB interface circuit sends the data information scanned by the scanning circuit to the terminal device, and the status indicate circuit indicates different states according to different scanning results when the scanning circuit scans the target bar codes. The circuit for scanning codes has the advantages that a user can easily check the system status of the handheld screen scanner and the data informationof the scanned bar codes, and the effects of data transmission speed and transmission stability are improved.