In the informatization construction of three - level hospital, besides the improvement of the function and efficiency of the informatization system, we should pay more attention to the safety problems, ensuring the safety of the hospital informatization construction. Based on the author's own practical experience, this article firstly briefly analyzes the necessity of risk prevention, and then analyzes the existing security risks in informatization construction in three - level hospital. Finally, it puts forward the corresponding measures and suggestions, hoping to provide reference for the relevant work.