Belonging to the field of petroleum drilling, the invention discloses a mud cake mechanical property measuring instrument. The mud cake mechanical property measuring instrument comprises: a high temperature and high pressure kettle, a metal cylinder group, a first tensiometer, a second tensiometer and a torque motor. The high temperature and high pressure kettle is a cube structure provided with a cavity, the bottom is provided with a semicylindrical groove for generating a mud cake, the metal cylinder group is disposed in the semicylindrical groove and consists of a first metal cylinder, a second metal cylinder and a third metal cylinder, the height direction of the metal cylinders is parallel to the length direction of the semicylindrical groove, the diameter is smaller than that of the semicylindrical groove, and the side contacts the mud cake. The first tensiometer measures the mud cake friction, the second tensiometer measures the mud cake adhesion, and the torque motor measures the mud cake torque. The semicylindrical groove simulates the well wall state, and the metal cylinder group simulates drill columns. The mud cake mechanical property measuring instrument provided by the invention solves the problem that the mud cake friction and adhesion cannot be measured directly, and reaches the effect of direct measurement of mud cake torque, friction and adhesion.