To provide a disc type valve unit to to prevent generation of a water hammer without deteriorating operation performance and design performance of a single lever type combination faucet.

Above a fixed valve plate provided with a cold water feed hole, a hot water feed hole, and a water discharge hole, a movable valve plate is provided, having a hole connected to the water discharge hole in the fixed valve plate, that is interlocked with an operation lever to slide on an upper surface of the fixed valve plate to be connected to the cold water feed hole and the hot water feed hole. By adjusting the matching degree of the holes in the valve plates, hot water-to-cold water quantity ratio and flow quantity can be set in this disc type valve unit. Moving speed of the movable valve plate is set variable to moving speed of the operation lever, so that the movable valve plate at the instant when the hole in the fixed valve plate and the cold water feed hole and the hot water supply hole in the movable valve plate are closed slower.