An acceleration sensor module, installed in a front region and/or a side region of a vehicle, includes a sensing section and an adjusting section. The sensing section includes a capacitive detecting section and a converting section. The detecting section detects the acceleration of the vehicle. The converting section converts a capacitance value into a voltage value. The adjusting section includes an AD converter, a communication circuit, a power source section, and an oscillator. The AD converter converts an analog output of the converting section into a digital value. The communication circuit sends an output of the AD converter to a collision judging section. The power source section supplies electric power to each of the AD converter, the communication circuit, and the sensing section. The oscillator supplies the clock to the AD converter and to the converting section of the sensing section.