An assembled method about an electrical connector comprises the following steps: A. providing a housing received a plurality of terminals and defined a housing hole; B. providing a cover defined a cover hole thereof; C. mounting the cover on the housing and making the housing hole in alignment with the cover hole; D. providing a cam defined a end surface and a riveting plate for riveting the cam; E. inserting the cam into the cover hole, the housing hole and riveting hole in turn; F. using the pressing header riveting the end surface of the cam; in addition, the assemble method further comprises the step G: defining a recess with the shape similar to the shape of the pressing header.