A system for medical imaging is provided. The system includes a scanning device configured with a scanning cavity, a control device, and an output device configured within the scanning cavity. The control device is configured to obtain one or more scan protocols and acquire at least one guide instruction corresponding to the one or more scan protocols. The output device is configured to obtain guide information corresponding to the at least one guide instruction and present the guide information. The scanning device is configured to scan a subject with the presentation of the guide information according to the one or more scan protocols.