The invention provides a coupler uncoupling control mechanism which comprises an uncoupling cylinder, a pushing cylinder and a control assembly, wherein the pushing cylinder is connected with a first valve body; the first valve body comprises a first air inlet capable of being connected with a main duct of a train, a first air outlet communicated with the first air inlet, a second air inlet and a second air outlet communicated with the second air inlet; the first air outlet is communicated with an air inlet chamber of the pushing cylinder, and the second air inlet is communicated with an air outlet chamber of the pushing cylinder; the control assembly comprises a second valve body which is a pneumatic control valve; the second valve body comprises a third air inlet capable of being communicated with an uncoupling duct of the train, a third air outlet communicated with the third air inlet, and a first control port capable of controlling ventilation between the third air inlet and the third air outlet after triggering; the third air inlet is communicated with the air inlet of the uncoupling cylinder; and the first control port is connected with the first air outlet of the first valve body. The coupler uncoupling control mechanism provided by the invention can ensure smooth uncoupling of an electric coupler.