To provide a connector, which can prevent backlash between a connector housing and a case, and which does not generate a gap between right and left split-type cases when the split-type cases are closed.

A connector 10 comprises a cylindrical connector housing 30 fitted with a mating connector, and a case 20 formed of two split-type cases 20a, and having a housing fixing part 21 fixing the connector housing to each of the split-type cases. The connector is provided with a thick rib 21C, on the outer edge of which the housing fixing part is formed. An inner peripheral groove 21M is formed on the thick rib, and plural vertical protrusions 21V extending in an insertion direction of the connector housing are formed on at least one side wall of both vertical side walls forming the inner peripheral groove. The connector housing is provided with a peripheral rib 30M formed on an outer periphery across 360 degrees almost at a center in an axial direction. The peripheral rib is engaged with the inner peripheral groove 21M by smashing a top part of the vertical protrusions 21V.