To provide a fluid injection apparatus which is simply structured and can lock a carriage in a maintenance position of a fluid injection head.

The fluid injection head is provided with: a recording head injecting ink; a carriage reciprocatable back and forth and supporting the recording head; a lead screws 31 and 32 rotating in constant positions, following generation of a driving force; moving members 41 to 43 linearly moving following rotations of the lead screws 31 and 32; a maintenance member for carrying out a maintenance for the recording head; and a locking member 59 for locking the carriage when the carriage moves to a home position HP being the position where a maintenance for the recording head is carried out by the maintenance member. The locking member 59 is constituted to move between a locking position to lock the carriage and a non-locking position not to lock the carriage, by a driving force given by a linear movement of the moving member 41.