Abstract: A portable valve seat grinder and method of its use is disclosed. The portable valve seat grinder comprises a body element with a longitudinal hole there through, with bushings mounted in the longitudinal hole. The body element has screw threads on one end thereof which are of a proper pitch and diameter to mate with those on fluid flow control valves or an adaptor. The portable valve seat grinder also comprises a shaft, to one end of which is securely attached a grinding element. The shaft with attached grinding element is mounted in the body element by sliding the shaft into the bushings such that the grinding element is positioned near the screw threads on the body element. The outer surface of the body element can be knurled to aid with handling during use.