The invention discloses a remote diagnosis system of a medical section, comprising a microscope, a camera, a video coder, a server and a client computer; the microscope, the camera and the video coder are connected with the server sequentially, the camera is connected with the server which is connected with the client computer by network. The invention also discloses a remote diagnosis network transmission method of a medical section, comprising the following steps: (1) initial setup is that a complete section is acquired under a low-resolution acquisition high compression ratio encode mode; (2) diagnosis is carried out by doctors, a pathological region is found, a high-resolution acquisition low compression ratio encode mode is set to obtain a high-quality image; image effect is adjustedand is stored, display is carried out in a real-time matching way, and then a medical certificate is sent down; (3) if the diagnosis is not carried out, the state is set back into the initial state, other pathological regions are found to continuously diagnose. The invention has the advantages of simple structure, low cost, and obtaining a dynamic low-quality image and a static high-quality imageof the pathological region under low bandwidth.