A lamp holding apparatus for mounting a lamp to a lamp mounting member includes a mounting plate provided with a locking portion which protrudes to a base side, inserted into a mounting hole provided at the base and is lockable to a peripheral edge of a back side thereof. The mounting plate is provided with a pin which protrudes to an opposite side from the base side and is capable of being gripped by an operator at a time of being attached to and detached from the base. The locking portion is disposed at a position corresponding to a back side of the pin. As a result, when the locking portion is inserted into the mounting hole while gripping the pin, both the locking portion and the mounting hole are easily positioned. Thus, at a time of insertion, bending forces are reduced.