A waterproof connector includes a female connector housing and a cylindrical packing holder. The female connector housing has a peripheral edge of an opening through which a male connector housing is inserted. The packing holder has a peripheral edge of an opening. This peripheral edge contacts the inside of the peripheral edge of the opening in the female connector housing. The peripheral edge of the opening in the packing holder has end portions formed by partially cutting the packing holder. Recesses are formed in the end portions on the peripheral edge of the opening in the packing holder. Projections are formed on portions of the female connector housing, which portions correspond to the end portions of the packing holder. The projections are fitted into the recesses so as to join the packing holder and the female connector housing. When the packing holder is inserted into the female connector housing, the peripheral edge of the opening in the packing holder is joined integrally with the peripheral edge of the opening in the female connector housing. Thus, when the male connector is fitted, it is mated smoothly with the female connector housing without causing the end portions of the peripheral edge of the packing holder to hinder mating.