The aim of this study is to design a plantar pressure testing device based on a multi-functional training bed with the back-support weight reduction function, and the device can be used for the training and assessment of rehabilitation of lower limb. Plantar pressure test is implemented by installing two foot plantar pressure sensors on each pedal board. The sensors are connected through the conditioning circuit, respectively with sensor interface circuits, and transfer the signal to the computer through data acquisition device. Then the host computer process and output related information. The system is accurate and reliable, with important clinical value.