The invention discloses a hybrid chaotic LPI (Low Probability of Interception) communication system design method. According to the method, firstly, sequence chaotic system design of a digital communication system is implemented, a digital chaotic sequence is generated, simultaneously, according to characteristics of a channel, generation of carrier continuous chaotic signals is implemented, and by cascading of the digital chaotic sequence and continual chaotic signals, design of a hybrid chaotic system is implemented; and a receiving end firstly implements detection of the continuous chaotic signals, generates a digital sequence and then implements demodulation of a discrete chaotic sequence. Digital chaotic time domain waveforms and frequency domains of the continuous chaotic signals have flatness and are similar with a spectrum of noise, and thus, the continuous chaotic signals have the very high hiding characteristic; and power spectra of the continuous chaotic signals are very similar with that of the environmental noise and meanwhile, are very low in probability of interception, and thus, implementation of cascading of the continuous chaotic signals and the digital chaotic sequence greatly improves hiding performance to a certain degree.