The Jinzhai earthquake swarm began to be active since August 2014 and then a series of inductive small-medium earthquakes occurred. According to the descriptions by the local residents,the earthquakes with the magnitude greater than M_L ≥ 1.0 can be clearly felt,accompanied by brontides. As a result,it's necessary to study the accurate focal depth of the swarm. Focal depth phase sPL is applied to calculate the focal depth of this swarm and the result shows that the focal depth of 16 events is within 5km,shallower than the Huoshan M_S4.3 earthquake which is in the same fault with the swarm and Tongcheng M_S3.6 earthquake. In addition,hypoDD method is used to relocate the swarm and then obtained the expansion coefficient on the basis of relocation result. The expansion coefficient is 0.27m²/s close to the results of Longtan and Xiaolangdi's. According to the characteristic of the Jinzhai earthquake swarm,a preliminary analysis of seismogenes was carried on and got a conclusion that the swarm may be related to the reservoir.