The invention relates to the field of trains, and provides a coupler clamping device and a control method thereof. The device comprises a mounting base, a moving shaft, a sleeve, a first clamping jaw,a second clamping jaw and a plurality of pressure monitoring assemblies. The first clamping jaw and the second clamping jaw are oppositely arranged, and a plurality of mounting holes used for mounting the pressure monitoring assemblies are arranged in clamping surfaces of the first clamping jaw and the second clamping jaw; and each pressure monitoring assembly comprises a pressing column, a pressure sensor and a reset piece, the reset piece is arranged between the pressure sensor and the pressing column, a first end of the pressing column extends into the mounting hole, and a second end of the pressing column extends out of the mounting hole. The control method comprises the following steps: judging whether each detection value is smaller than a preset pressure value or not, counting thenumber Y of the detection values smaller than the preset pressure value, and if Y is equal to N, starting an alarm; and judging whether each detection value is equal to zero, counting the number Z ofthe detection values equal to zero, and if Z is greater than zero, starting the alarm. In the invention, multi-point monitoring is realized, and accuracy of a monitoring result is significantly improved.