To keep a seating posture without a hip numbness even at the long driving time without a physiological posture change.

This seat 1 is composed of a cushion material covered by a cuticle material 8. The cushion material consisting of plural blocks 3 obtains a body pressure distribution data at the seating time in advance and finds out the area of an excessive load by seating for a long time. An air bag 2 is arranged integrally with the blocks 3 on the lower part of the block 3 positioned to the area of the excessive load, out of plural blocks 3. A pipe body 6 is communicated in the air bag 2 and connected to an air pump 4 driven and controlled by a controller 5. By taking the air in/out to/from the air bag 2 of the block 3, each position of a body pressure distribution when the weight of a seating person M is applied to the vehicular seat 1 is changed forcedly at every certain time.