A connector assembly is provided which includes a first connector having a first housing and a second connector having a second housing. The first housing has two fixed portions positioned apart from one another in the transverse direction, an elastic portion passing between the two fixed portions and able to bend elastically in the longitudinal direction, and an engaging protruding portion formed on the elastic portion and able to be hooked in an engaging hole in the second housing. The engaging protruding portion is positioned between upper and lower edges of the elastic portion.