Provided is a vehicle door structure that enables manufacturing cost reduction and weight reduction. A vehicle door structure 1 includes a lock mechanism 40. The lock mechanism 40 locks sliding of a slide door 6 in a fully closed position in which the slide door 6 closes a door opening portion 4 and in a fully open position in which the slide door 6 fully opens the door opening portion 4. The lock mechanism 40 includes the portion to be locked 50 provided to the guided body 18 and the locking portions 60 and 70 provided to the slide rail 17. The portion to be locked 50 protrudes toward the locking portions 60 and 70 and is locked by the locking portions 60 and 70 in the fully closed position or the fully open position.