In order to determine the optimum location for entry of the lower No. 3 coal seam with the variable seam spacing and close coal seams of Meihuajing coal mine in Ningxia, by combining the 5 interlayer boreholes information of the lower No. 3 coal seam and the 232204 panel face in the upper No. 2 coal seam, the failure range of the floor after the upper No. 2 coal seam mining is explored through theoretical analysis, field monitoring and numerical simulation. The fracture development regularity and stress distribution characteristics of the floor with information of 5 interlayer boreholes after the upper coal seam mining are analyzed, and the optimum location for entry is determined. The main conclusions are as follows: 1) the maximum failure depth of the floor with information of 5 interlayer boreholes is 19.57 m and the lower No. 3 coal seam is basically disturbed by the mining of the upper No. 2 coal seam. 2) the inverted trapezoidal zone appears in the fracture development areas with variable spacing mining, and the maximum horizontal distance between the stress-relaxation area and boundary pillar is 9.69 m. 3) The entry of lower coal seam is arranged with an inner stagger distance of 15 m considering a 1.5 safety factor and a scheme of partition entry support under variable layer spacing conditions is proposed. The results can provide a reference for the layout of entry with similar conditions.