To apply a gate valve even to a buried pipe of thin earth covering by arranging the guide block part to movably engage with the guide part in a female screw member to threadedly engage with a valve rod in the direction orthogonal to the moving direction of a valve element.

A valve element 4 moves up to a fully closing position shown by a continuous line by passing through an intermediate position shown by an imaginary line by moving in the closing direction along a guide rail 6 by rotating a valve rod 9 in the valve opening direction. Thus, when the valve element 4 moves to the fully closing position, a female screw member 12 is put in a state of being positioned in the upper end part of the valve rod 9, and the guide block part 13 is put in a state of being positioned in the upper end part of a guide groove 7, respectively. Therefore, a gate valve can be used without a problem even if earth covering of a buried pipeline becomes thin since a position of a cap engaged with a valve key can be largely lowered than usual. That is, the gate valve can be reduced by about a height dimension of the valve element housing part 3 more than a conventional one since the valve element housing part 3 can be arranged on the side of the valve seat 2 part.