The invention discloses an automatic testing device. The device comprises a motor base. The middle part of the motor base is provided with a pneumatic gripper for fixing to-be-tested parts; a first pushing mechanism is arranged on the left side of the pneumatic gripper of the motor base; and a second pushing mechanism is arranged on the right side of the pneumatic gripper of the motor base. A first connection mechanism for connecting a testing instrument to test the to-be-tested parts is arranged between the first pushing mechanism and the pneumatic gripper; a second connection mechanism for connecting the testing instrument to test the to-be-tested parts is arranged between the second pushing mechanism and the pneumatic gripper; and the first pushing mechanism and the second pushing mechanism move to drive the first connection mechanism and the second connection mechanism to move towards the to-be-tested parts respectively. The automatic testing device automatically tests parts and greatly improves the testing efficiency; moreover, the first pushing mechanism and the second pushing mechanism push the first connection mechanism and the second connection mechanism to be automatically connected with two ends of the to-be-tested parts accurately and the alignment is accurate, so a testing error caused by inaccurate alignment can be avoided.