Abstract: In order to master the abutment pressure distribution and its influence scope of the fully mechanized caving face stop line, we analyze a reasonable coal pillar width which both can meet the needs of roadway maintenance and reduce the loss of coal pillar as much as possible. We dynamically monitor the stress changes of coal pillar and roadway surrounding rock loose range through arranging stress and the coal body loose scope observation areas at fully mechanized caving face return air lane. The results show that the maximum stress readings is 3.90 MPa and minimum is 2.50 MPa, which suggest that the coal pillar width within 50 m to 170 m is reasonable by abutment pressure, and the coal pillar width of stopping line could be reduced to 160 m.