A connector assembly includes a first connector and a second connector mating with the first connector. The first connector defines a first mating face, a first cleaning device disposed in the first mating face and a stiff first mating portion exposed upon the first mating face. The second connector defines a second mating face, a second cleaning device disposed in the second mating face and a stiff second mating portion exposed upon the second mating face. During mating the first connector to the second connector along the mating direction, the first cleaning device wipes the second mating face for wiping away the dirty attached to the second mating portion while the second cleaning device wipes the first mating face for wiping away the dirty attached to the first mating portion until the first and second mating portions mated with each other.