A vehicle seat may include a seat main body, a rotation mechanism that is arranged and constructed to horizontally rotate the seat main body between a forwardly facing position and a laterally facing position, a sliding mechanism, and a rotation locking mechanism. The rotation locking mechanism is arranged and constructed to prevent the seat main body from rotating when the seat main body is in a laterally facing position. The rotation locking mechanism includes a first engagement portion, a second engagement portion, and a lock releasing portion. The second engagement portion is capable of moving between a condition in which it does not engage the first engagement portion and a position in which it engages the first engagement portion when the seat main body is in the laterally facing position. The lock releasing portion is arranged and constructed to be engaged with and disengaged from the second engagement portion depending upon the sliding motion of the sliding mechanism.