The invention belongs to the field of automobile manufacturing and particularly relates to a device and method for testing the durability of an internal lock lifting button of an automobile door. The device comprises a base frame, a first upright post, a transverse post, a second upright post and an air cylinder, wherein the base frame is of an H-shaped structure; the first upright post is arranged at the three-branch intersection of the base frame and orthogonal with the base frame; the transverse post is connected with the first upright post and parallel to the base frame; a convex end is arranged on the transverse post; the second upright post is connected with the convex end of the transverse post; the first upright post is connected with the automobile door through an automobile door hinge; the air cylinder is arranged on the second upright post; and the motion track of the tip of an air cylinder piston and the internal lock lifting button of the automobile door are located on the same track. Manual operation can be replaced with the device for testing the durability of the internal lock lifting button of the automobile door to achieve durability testing of the internal lock lifting button of the automobile door, the device is not limited by time and temperature, is wide in application range and can operate for a long period of time, the production efficiency is greatly improved and the human cost is reduced.