To provide a liquid manifold device designed for allowing uncontrollable misalignment generated in connection between manifold parts of two pumps and forming a seal hardly causing leakage in this connection state.

A manifold device for connecting adjacent to pumps 10, 12 is provided with two-piece structure manifold parts 22, 24. The manifold parts 22, 24 independently connected to liquid pumps is firmly screwed and fixed to pumps 10, 12 in the position in which the manifold parts 22, 24 are most accurately positioned mutually. Then, the manifold parts 22, 24 are fixed mutually via a screw hole in one manifold part 24 by means of a fastening member 40. The hole is larger than a screw hole in the other manifold part 20. Because of this large hole, a predetermined amount of misalignment is allowed while the manifold parts 22, 24 are firmly connected together sealably.