To provide an interference checking method of a robot for preventing the collision of the robot by surely checking an interference between approximate solids.

This interference checking method of the robot comprises a means 91 for arithmetically operating a distance between the approximate solids from positions of the approximate solids set in a plurality of robots, and an interference determining means 92 for comparing preset sizes of the approximate solids with the distance between the approximate solids arithmetically operated by the means 91, and comprises a distance storage means 12 for storing at least one of distances between the approximate solids arithmetically operated by the means 91, and a position storage means 11 for storing at least one of the positions of the approximate solids, and comprises an interference predicting means 13 for predicting the interference of the robots from the sizes 93 of the approximate solids, the distance 106 stored in the distance storage means 12, the distance 906 between the approximate solids, the positions 104 and 105 stored in the position storage means 11 and the positions 904 and 905 of the approximate solids.