Occupant protection apparatus for vehicle

The invention provides an occupant protection apparatus for starting or stopping a pre-tightening device according to collision conditions so as to inhibiting the rising of harm to an occupant. The occupant protection apparatus for a vehicle includes a door sensor (21) that detects a defamation of a side door (DFL) in a side collision and an occupant position detection sensor (24) that detects a lumbar position of the occupant. A pretensioner is activated when it is determined from detection by the door sensor and the occupant position detection sensor that an intruding-object collision rear-end position in the side door is located in front of the lumbar position, and the pretensioner is prohibited from activation when it is determined that the intruding-object collision rear-end position is not located in front of the lumbar position. When there is a possibility that a clearance between the lumbar of the occupant and the deformed side door is insufficient, the pretensioner is prohibited from activation to al