To provide a human error preventing valve in which the valve is properly operated as a result even though a person erroneously operates a valve during emergent time such as earthquake, fire, lifesaving, and the mechanism of the same.

A handle and a shaft of a valve are integrally formed and the valve is directly moved by the shaft up to now. Consequently, it is sometimes experienced that the valve is erroneously moved in a reverse direction even though opening/closing is shown during emergent time. A handle shaft and a valve shaft are arranged in the valve, two gears are arranged in the handle shaft and the two gears are arranged in the valve shaft, the power transmitting system of the handle shaft is constituted of two systems, one-way clutches are arranged between the two gears of the handle shaft and the shaft such that the locking directions are different, and an one-way clutch is arranged between the valve shaft gear and the shaft, thereby two-way rotation input is changed to one-way rotation input, consequently erroneous operation does not cause secondary disaster.