Abstract: This paper aims to effectively prevent rock burst accidents occurs because of the roof caving with the old roof periodic weighting in fully-mechanized sublevel caving mining face.It uses the mining examples of fully-mechanized sublevel caving mining in 1305 working face of Dongtan mine and adopts a new generation SOS microseism monitoring and measuring system.The system was made in Poland Mining Research Institute.It was developed to full time monitoring and measuring on the working face since the beginning of working face interconnection.The paper analyzes statistically the micro earthquake events,incident frequency and event total energy periodic changes.Thus it deduces the old roof fracture periodicity.Afterwards,it proves the accuracy of the system through theoretical calculations.The results show that there is a corresponding relationship between the working face periodic weighting and event total energy periodic changing. Before the strong micro-seismic activity occurred,there would be a weak seismic activity period and the weak seismic activity would play energy accumulation role to the strong seismic occurred.Releasing of the total energy in periodic weighting fluctuates in a certain range fluctuations,but the instability of fluctuation changes enhanced.The conclusion has certain actual significance for the working face safety mining and preventing the occurrence of mining-induced earthquakes.