The invention discloses an optimization method for a contact shape of a disconnecting switch. The method is characterized in that the method comprises using an ANSYS Maxwell platform to perform electrostatic field simulation analysis on a disconnecting switch, and then performing parameterization analysis on a contact finger of the disconnecting switch, and compiling a least square method curve-fitting program to process a numerical value obtained by parameterization, to obtain an electric field extreme point, a chamfering value of the obtained electric field extreme point being an optimal chamfering value. Performing chamfering on the touch finger of the disconnecting switch according to the optimal chamfering value can obtain a final optimized contact shape of the disconnecting switch, so as to realize optimization of the touch structure of the disconnecting switch, and the structure of the disconnecting switch is optimized, and effects of reducing electric field intensity of the disconnecting switch and reducing isolation faults of the disconnecting switch are achieved.