Campus security is a very important part of smart campus. How to conduct comprehensive, real-time, efficient and accurate campus security monitoring is a key issue among them. At present, the monitoring method commonly used in colleges is video surveillance, which has the disadvantages of blind spots, easy to be blocked, easy to be affected by factors such as weather and visibility, and not easy to realize automation and intelligence. This paper proposes for the first time the use of microseismic signals for campus security monitoring in the smart campus, using distributed fiber optic acoustic sensing technology (DAS) as the monitoring method, and proposed corresponding detection algorithms. Distributed fiber optic acoustic sensing technology uses optical fibers as sensors to detect changes in microseismic signals, thereby detecting the surrounding environment. Compared with traditional methods, DAS has the advantages of high sensitivity, strong real-time performance, anti-interference, no obstruction, easy deployment, and low cost. This paper also carried out on-site detection experiments of campus security, focusing on several directions such as emergency detection, vehicle location, over speed warning and congestion warning, and obtained experimental results. According to the experimental results, the detection accuracy of campus security incidents is relatively high, so this method has strong practical significance.