This paper mainly discusses on the design of the motorcycle alarm with an ultra- low power single- chip MSP430G2855 for the control chip. The Internet of things is built through cloud server, mobile phone APP, and the GPRS module of alarm. With cooperative work of vibration sensor and ultrasonic sensor, the ultrasonic sensor doesn’t work to reduce power consumption if the vibration sensor detects no signal. At the same time, ultrasonic sensor is used to distinguish whether someone is approaching, reducing the probability of false alarm. Based on the Internet of things, users can handle false alarm signal through mobile phone APP and track stolen motorcycles.