A valve block and a valve block unit which allow simplification and miniaturization of a pipe arrangement. The valve block includes at least one flow switching valve including a valve body, the valve selectively switching between conductions of a fluid (heat medium), a first pipe (heating outward-flow main pipe) and a second pipe (cooling outward-flow main pipe), switched by the flow switching valve, allowing the fluid to be conveyed therethrough, and a third pipe (first branch pipe) that selectively communicates with the first pipe or the second pipe, the flow switching valve, the first pipe, the second pipe, and the third pipe being connected to each other.