A retainer 30 of an electrical connector has first and second stopping protrusions 37,38 protruding from the anterior edges of a pair of bendable members 35 and 36 located on the sides thereof. A third stopping protrusion 39 also protrudes from a location below the second stopping protrusion 38. When a retainer 30 is pushed into a final position in a retainer insertion hole 14, the first stopping protrusion 37 and the third stopping protrusion 39 are engaged by a pair of receiving members 18 and 19 located in the retainer insertion hole 14. In this manner the retainer 30 is maintained against removal even if tipped at an angle or subjected to an oblique force. Similar effects apply when the retainer is in a temporary position.