Abstract: In order to explore the new characteristics of the mine pressure behavior and roof activity of the working face after the length of the fully mechanized coal mining face has been significantly extended, taking the first 450 m super long working face in the medium thick coal seam in China as the engineering background, based on the support pressure and micro-seismic real-time monitoring means, the support resistance distribution, resistance increase characteristics and micro-seismic energy distribution characteristics of super long working face are comprehensively analyzed. The research results show that after the length of the fully mechanized mining face is lengthened from 300 m to 450 m, the distribution characteristics of the support resistance along the dip change from single peak to double peak, the support strength of the working face increases by an average of about 7%, and after the working face is lengthened, the ground pressure intensities of the working face is enhanced as a whole. The resistance increase of the support during the weighting period of the super long working face is mainly in the form of “logarithmic−exponential” composite function, which is characterized by rapid resistance increase at the beginning, slow resistance increase in the middle, and rapid resistance increase in the last short time. The large cutting depth mining of super long working face is the main inducement for the rapid increase of support resistance at the end of coal mining cycle. The cutting depth of the shearer should be appropriately reduced and the support quality should be improved when the roof state is unstable. The energy and frequency of micro-seismic events of overburden breaking in the working face are small and low, and they are mainly active in the range of 40 m behind the working face to 80 m in front of it. The distribution characteristics of micro-seismic events show that the roof of the super long working face can collapse in time, and there is no long-distance hanging phenomenon, which is not easy to cause strong dynamic load events. In the vertical direction, the micro-seismic events are mainly distributed in the roof below 25 m in vertical height. The basic roof of fine sandstone with a thickness of 17.82 m is the leading rock stratum that causes the mine pressure behavior of the working face. The breakage of the high level rock stratum has little impact on the mine pressure behavior of the working face.