A connector includes a housing and a holder. The housing includes a terminal housing chamber housing a terminals and a support portion in which a first locking portion for locking the holder in the temporary locking position is formed. The holder is mounted on the housing so as to be movable in a fitting direction of the housing and a mating housing between a temporary locking position and a main locking position. The holder is configured to be immovable from the temporary locking position to the main locking position when the terminal inserted into the terminal housing chamber is in a halfway insertion position and is configured to be movable from the temporary locking position to the main locking position when the terminal is in a normal insertion position.