A waterproof connector has a housing formed with holding portions capable of holding terminal fittings, and formed at one end with a fitting hole into which electric wires connected to the held terminal fittings are inserted; a waterproof plug having first electric wire insertion holes corresponding to the holding portions and fitted into the fitting hole; and a holder having a body portion preventing the waterproof plug from detaching from the housing and provided on the opposite side of the waterproof plug to the terminal fittings. The body portion of the holder is formed with second electric wire insertion holes into which the electric wires inserted into the first electric wire insertion holes are inserted. Further, the body portion is formed integrally with fitting protrusions that fit into the unused first electric wire insertion holes, thereby preventing drops of water from entering the housing through the unused first electric wire insertion holes.