To provide a connecting structure of vacuum evacuation devices capable of suppressing pressure loss due to piping and saving space and reducing costs.

The plurality of vacuum evacuation devices (1A, 1B, 1C) include pump chambers (21C, 22C, 22B, 23B), further include intake ports (32B, 33B) and exhaust ports (41C, 42C) each connected with any of the pump chambers, and have the connecting structure to communicate the pump chambers with each other when the vacuum evacuation devices are disposed in direct communication with each other. The connecting structure of the vacuum evacuation devices has connecting means (7) including at least one main connecting passage (78) for allowing a gas exhausted from the vacuum evacuation device (1C) disposed at the other side, to flow to the vacuum evacuation device (1B) disposed at one end side, by directly connecting the plurality of vacuum evacuation devices, and connecting the intake port of the vacuum evacuation device (1B) of the plurality of connected vacuum evacuation devices that is disposed at one end side and the exhaust port of the vacuum evacuation device (1C) disposed at the other side.