The invention provides an impedance matching method, an impedance matching device and semiconductor processing equipment. The impedance matching method comprises the following steps: S1, the first regulating quantity of a driving mechanism is acquired; S2, the position of the driving mechanism is regulated; S3, the actual position of the driving mechanism is acquired; S4, whether the actual position of the driving mechanism reaches an expected position is judged, if not, a second regulating quantity of the driving mechanism is acquired, the second step is carried out, and if yes, a fifth step is carried out; S5, whether load impedance and output impedance of a radio frequency power supply are matched is judged, if yes, a sixth step is carried out, and if not, the first step is carried out; and S6, whether the process is ended is judged, if not, the fifth step is carried out, and if yes, the process is ended. The impedance matching method can avoid the problem of matching point drift, and the stability, the reliability and the repeatability of the impedance matching device are thus improved.