The present invention relates to a tank car image identification system. The tank car image identification system comprises a depth detection device connected with a data compositing device and used for receiving an instant composite image, determining a depth image corresponding to the instant composite image and determining the depth information of the instant composite image based on the depthimage; an edge detection device connected with the depth detection device and used for receiving the depth information of the instant composite image and determining a target edge in the instant composite image based on the depth information of the instant composite image; and an edge enhancement device connected with the edge detection device and used for carrying out the corresponding edge enhancement processing on the instant composite image based on the target edge in the instant composite image to output a corresponding edge enhancement image. According to the present invention, the situation that the oil gas in a tank car is stolen by the Illegal personnel can be avoided effectively.