To provide a connector capable of surely guiding in fitting, even in small and multipole connectors and having housing strength necessary for insertion and removing.

A fitting space 13 surrounded by a plate-shaped sidewall 12 made of an electrical insulating material is formed in a plug housing of a plug connector 1, and a receptacle housing 50 is accepted within the fitting space 13 for fitting. A guide part 12d for guiding the receptacle housing 50 when the receptacle housing 50 is accepted for fitting is formed in the plate-shaped side-wall 12, and the outermost side of the guide part 12d is formed with frame ground metal fixtures 40, 40 for reinforcing the plate-shaped sidewall 12, when the receptacle housing 50 is inserted and removed.