A type of ZK-worm gearing with ZA-worm wheel in the state of mismatched point contact ispresented. A method to machine and modify the toothprofile of the worm by adjusting parameters for machine tool setting and cutter is proposed. It is provedby experiments that this type of worm gearing even inthe conditions of the center distance errer of ± 0.5mm. is as good as the convnetional conjugated ZK-worm gearing.