Objective In order to detect the change of respiratory function induced by respiratory diseases at early stage, a multiple-channel respiratory monitor system based on electrical impedance technology is developed to monitor the electrical impedance signal of thorax and abdomen. Methods The system is composed of three parts: an electrical impedance acquisition unit, a multiple-channel switch and a control unit. The electrical impedance acquisition unit can generate constant sinusoidal current and measure the electrical impedance using four-electrode method, and the control unit can control the multiple-channel switch to measure the impedance signal of thorax and abdomen alternately using the same electrical impedance acquisition unit. An experiment is conducted on 5 healthy persons, and the electrical impedance of thorax and abdomen respiration before and after the five-kilometer running is captured by using this system. Results The synchronization of electrical impedance signal of thorax and abdomen respiration before running is significantly different from that after running (P<0.01). Conclusions The system can monitor the electrical impedance signal at different sectors of human body and is potential in diagnosis of early respiratory diseases.