The invention discloses a mechanical state evaluation method for an isolation switch. The mechanical isolation switch state evaluation method comprises steps that 1), multi-point vibration signals during present motion of the isolation switch are acquired through a vibration acceleration sensor, and the current information of a driving motor during the present motion of the isolation switch is acquired through a current sensor; 2), an autocorrelation function Rv(tau) of the multi-point vibration signals during the present motion of the isolation switch and an autocorrelation function Ri(tau) of the current information of the driving motor during the present motion of the isolation switch are calculated; 3), power spectrum density PSDv of the multi-point vibration signals during the present motion of the isolation switch is calculated according to the autocorrelation function Rv(tau), and power spectrum density PSDi of the current information of the driving motor during the present motion of the isolation switch is calculated according to the autocorrelation function Ri(tau); 4), a transfer function |H(omega)1| during the present motion of the isolation switch is acquired; and 5), a transfer function |H(omega)2| during a next motion of the isolation switch is acquired, a correlation coefficient rho is then calculated, and a mechanical state of the isolation switch is evaluated according to the correlation coefficient rho. The method is advantaged in that the mechanical state of the isolation switch can be accurately evaluated.