A vehicle occupant protection system includes: a seat belt apparatus
including a shoulder belt (11) and a lap belt (13); an upper air bag (27,
113); a lower air bag (29, 67, 73, 83); and an inflation limiting
structure (37, 53, 55, 57, 75, 85) which is provided in the lower air bag
and limits inflation of a part of the lower air bag in a vehicle
back-and-forth direction when the lower air bag is inflated. When the
vehicle collision is detected or predicted, the upper and lower air bags
are inflated and vertically come into contact with each other. Further,
an upper part (41, 71, 79, 91) of the inflated lower air bag positioned
above the inflation limiting structure is pressed by the upper air bag
and bends toward the front of the vehicle at the inflation limiting
structure.