With the continuous development of modern industrialization, we use vacuum pumps more and more frequently. Oil return often occurs during use, which has also caused some troubles to our enterprise's development and production. Next, I will analyze the measures to prevent oil return of vacuum pump: 1. The static sealing part of shaft seal shall be firm and replaced in time. 2. Move the oil tank and exhaust valve to the side to reduce the oil level and reduce the amount of oil. 3. The plane of the vacuum pump base shall be flat, and the valve plate shall be elastic. 4. Separate the oil near the exhaust valve from other oil, and the oil level is only slightly higher than the partition wall. 5. Add a pipe into the oil hole so that the oil level is only slightly higher than the oil inlet. 6. The check valve mechanism of the vacuum pump is set to automatically close the oil inlet hole when the pump is stopped. 7. Set the oil pump and auxiliary mechanism to cut off the oil circuit when the pump is stopped. 8. Its pump port is equipped with an inflation valve. For the above small series, we provide measures to prevent the oil return phenomenon of vacuum pump. In the ordinary actual operation and use, doing these work well can effectively avoid the oil return phenomenon and ensure its normal operation.