In the process of hemodialysis, the patients' blood pressure and pulse wave are likely to change considerably so that hypotension and rapid heart rate may be dangerous to the hemodialysts' life. Based on the environment of hemodialysis room, we designed the communication system using SPCE061A single-chip computer and STC89C52 single-chip computer to realize wireless communication between upper system and the two single-chip computers, and on the upper computer the pulse wave can display at real-time and save data on the data base. At the same time we designed an interface program to reduce noise by way of frequency domain analysis and wavelet denoising. It can draw the cycle pulse wave, eigenvalue-K, the maximum peak and peak frequency, it can effectively judge a racing heart in the hemodialysis and can also evaluate vascular sclerosis of hemodialysis. In short, the system is able to improve treatment security and reduce the burden of the doctors and nurses in hemodialysis rooms.