In order to solve the problem of bag filter leak detection and location in the industry of cement production industry, a method for detecting and locating the broken bag based on fiber-optic distributed vibration sensing is proposed. Weak vibration signal can be detected as soon as dust air flows into the broken bag because of the high sensitivity of the vibration sensing system, and thus whether the bag is broken can be judged. A simulation is carried out, and the weak leak signal caused by dust air can been identified in the low-frequency range. In the laboratory environment, the maximum signal-to-noise ratio of the built phase-sensitive optical time domain reflectometry (φ-OTDR) is calculated to be 10 dB and the real spatial resolution is 23.7 m. In field trial, the support vector machine (SVM) algorithm is applied to distinguishing the abnormal bag from the normal one. The average recognition accuracy rate is tested to be 97.8%. The combination of φ-OTDR and SVM is capable of detecting and locating bag filter leak effectively.