Written communication is the communication between the two sides with the help of words, pictures, charts and other symbols. Written communication is an important form of doctor-patient communication. Paying attention to written communication in medical service is also an effective maintenance of the rights of both doctors and patients. Compared with language communication, written communication has low efficiency and long time, but it has many advantages, such as right and wrong, clear content, concrete and clear evidence, and it is also an important guarantee to maintain the doctor-patient relationship.