An adaptive balancing mechanism of dual-head cement trowelling machine includes a water tank, a screw support base, an adjusting screw, a sensor and controller, a counterweight, a stepper motor, an underframe, a guide rail, a guide rail support plate, limit plates, and a transmission member. The controller collects the weight change information of the water in the water tank in real time according to the operation process. Adjust the position of the counterweight in real time by the stepper motor and the adjusting screw to make the two trowel heads in adaptive dynamic balance to the ground pressure.