To provide a hinge with a locking mechanism capable of easily locking a door at a desired angle and unlocking the same.

In a hinge formed of a male piece and a female piece fitted between a door and a building to be used, one piece is provided with a guide rod, the other piece is provided with a penetrating hole, and the pieces are combined to open and close the door around the guide rod. One piece is provided with an L-shaped slit and a slide hole, a movable shaft having a lever and a spring are positioned in the slide hole, and a receiving hole allowing the movable shaft to go in and out of is provided in a designated position of the other piece. When the door is opened at a fixed angle, the movable shaft is inserted in the receiving hole to lock the door in a designated position.