Inertial positioning technology is one of the most important positioning techniques. It is suitable for environments without GPS, lack of radio base stations or have no priori geographic information. The pedestrian location system based on Micro Inertial Measurement Unit (MIMU) is usually integrated in the foot of the pedestrian and using the inertial law to solve the pedestrian's position, velocity and attitude information. What's more, the inertial location system utilizes the Zero Velocity Update (ZUPT) algorithm to suppress their errors. However, ZUPTs cannot effectively decrease pedestrian position errors and heading angle error. So pedestrian's position errors and heading angle error will still accumulate over time. Because the magnetometer can detect earth's magnetic field information and solving the heading angle by it, in this paper, a dual MIMU/ magnetometer/ ultrasonic pedestrian location scheme is proposed. The two MIMUs, two magnetometers and two ultrasonic modules are respectively fixed on the left and right foot of pedestrians, and the output information of magnetometer is used to assist the ZUPT algorithm to calculate the locating information, which suppresses positioning error and heading error. We use two ultrasonic modules to measure the spatial relative position relation of pedestrian's left foot and right foot in real time and construct the second order nonlinear constraint equation. We correct pedestrian position information continually by using this constraints so that to improve the positioning accuracy. To verify this program, in this paper, some experiments have been carried out. We have designed different pedestrian trajectories in certain building. After the experiment we processed and analyzed the offline data from this integrated positioning system. The experimental results show that compared with single MIMU pedestrian location scheme, pedestrian positioning technology based on dual MIMU/ magnetometer/ ultrasonic module has higher positioning accuracy, and the positioning accuracy of this system is better in the longer time, which can meet the requirement of pedestrian positioning where there is no external auxiliary information.