An automatic image-capturing system is used for capturing an image and transmitting the image to a remote device. The automatic image-capturing system includes a photography module for capturing the image; a storage module for storing the image captured by the photography module; a transmission module for receiving a control instruction sent by the remote device; a master core module for making the photography module to capture the image based on the control instruction, and segmenting the image into a plurality of files and segmenting the files into a plurality of packets to be transmitted to the remote device by the transmission module, and a slave core module for monitoring the operations of the master core module to turn off and restart the master core module when there is an abnormal operation in the master core module.