The utility model provides a vacuum pumping system of water ring pump and steam pump combination, includes the B1 booster pump, and waste gas gets into from the entrance of B1 booster pump, and through the B2 booster pump, the B2 booster pump links to each other with the C1 condenser, and the C1 condenser is linked together with the C2 condenser respectively through S3a jet pump, two pipelines inthe S3b jet pump, and the C2 condenser is linked together with the C3 condenser through two pipeline S4a jet pumps, S4b jet pump, C2 condenser top is passed through the exhaust tube and is inserted parallelly connected W4c water ring pump and W4d water ring pump, be provided with control flap on the pipeline on W4c water ring pump and the W4d water ring pump, the export and the atmosphere of C3 condenser communicate with each other, W4c water ring pump and W4d water ring pump export intercommunication atmosphere, the utility model discloses have the concise technology of fully provided, satisfy energy -efficient demand simultaneously.