In order to achieve low-cost and non-contact health monitoring, real-time monitoring of human breathing, heart rate and other physiological signals that are beneficial to disease prevention and health management without interference, a non-contact physiological parameter monitoring system based on piezoelectric ceramics is designed. The Piezoelectric ceramic sensor converts the pressure changes caused by human breathing, heartbeat and other weak vibrations into electrical signals, thereby obtaining the original physiological signals. The wavelet hard threshold algorithm is used to preprocess the original physiological signal, and the interference signal is filtered out by selecting the appropriate wavelet base, the number of decomposition layers and the hard threshold function. VMD algorithm is used to decompose the preprocessed physiological signal. According to the spectral distribution characteristics of each modal component after decomposition, the physiological signal is reconstructed to decompose the respiratory and BCG signal in the original physiological signal.Compared with the decomposing after the Butterworth filter is preprocessed, it has better performance. The experimental results show that the method can accurately separate respiratory signal and BCG signal, and can retain more spike BCG signal characteristics.