The study of swarm activity characteristics can provide effective basis for regional seismic risk analysis and seismic activity trend judgment. However,due to the influence of network layout and swarm location,some earthquakes are often missed,and the integrity of earthquake catalogue will affect the reliability of swarm activity characteristics analysis. Earthquake swarms have occurred frequently in North China since 2013,especially in Rushan,Shandong Province. More than 13000 small earthquakes were recorded in Rushan area on October 1,2013,and the maximum was M_L5.0 on May 22,2015. During this period,the seismicity increased and decreased for many times. In this paper,the GPU accelerated template matching method was used to scan the continuous waveforms recorded by the fixed stations and mobile arrays during the period from May 2014 to June 2015 of the Rushan earthquake swarm in Shandong Province. A number of 7500 earthquake events were detected,which was 4 times of the catalogue of the network,and the complete magnitude reduced from 1.0 to 0.2. Based on the completed earthquake catalogue,the activity characteristics of Rushan earthquake group were analyzed by using the model of infectious aftershock series(ETAS). The random components in ETAS model is used as the index of external force triggering earthquake. The Rushan earthquake swarm began to become intensively active in October 2013,while the Rushan array began to operate on May 5,2014. As a result,we added the detection catalogue to the earthquake catalogue of the whole Rushan earthquake swarm,divided the whole development process of the earthquake swarm into five active periods,and analyzed the seismicity of the Rushan earthquake swarm and its variation characteristics in each stage with the help of ETAS model. The results showed that the proportion of the earthquakes triggered by the external force of the Rushan earthquake swarm was large. Combined with the previous research results,it was preliminarily speculated that the fluid effect may be one of the factors of the external force and play a certain role in the development process of the Rushan earthquake swarm,but the triggering intensity of the external force on the microseismic activity was different in different periods.