Abstract: To study the impact hazard assessment of mining in the "knife−handle type" isolated island working face under the condition of both working faces being depleted by synchronously mining the coal pillar in the section along the empty remaining roadway. The FLAC3D numerical simulation analysis was conducted to study the schemes of synchronously mining the coal pillar in the section along the empty remaining roadway and the coal pillar in the non−mining section in the "knife−handle type" isolated island working face under the condition of both working faces being depleted by synchronously mining the coal pillar in the section along the empty remaining roadway. The dynamic changes and mechanical responses of the roof structure in the two main shafts and the goafs on both sides of the working face before and after mining were compared and analyzed to determine the optimal mining scheme for the N1103 isolated working face. The abnormal stress concentration areas before and after the mining of the N1103 isolated working face were clarified, and the impact hazard areas during the mining of the N1103 isolated working face were divided. The research results show that when the mining plan of the coal pillar in the non−recovered section is carried out, the remaining coal pillar in the section behind the goaf presents a large−scale support for the roof, which may cause a large−scale local overhanging roof. The sudden instability of the coal pillar may cause a high−energy mining earthquake event. The mining plan for the coal pillar in the recovery section avoids leaving bearing coal pillars in the goed−out area behind the working face, which is conducive to the timely collapse of the roof. However, the stress concentration in the triangular coal pillar area at the outlet of the working face increases. The mining side of the new transportation roadway is a coal pillar, and the stability of the surrounding rock is strongly affected by the coal pillar. Further pressure relief and advanced support need to be strengthened. Based on the analysis of the advantages and disadvantages of the two mining schemes, it is decided to adopt the mining scheme of the coal pillar in the recovery section. Meanwhile, anti−impact energy−absorbing hydraulic supports are used at the exit position of the working face to enhance the anti−impact support of the roadway. The comprehensive index evaluation method was adopted to determine that the impact risk level during the mining period of the N1103 isolated working face was a medium impact risk level. This research provides new ideas for the safe mining and impact hazard assessment analysis of irregular island working faces in mines with the same or similar conditions.