The vacuum liquid lock features include: it comprises a valve body and a sealing ball, where the inner diameter of the valve body is larger than the diameter of the sealing ball. The sealing ball is positioned within the inner cavity, which has an inlet and an outlet. The outlet of the inner cavity is a circular arc surface that matches the curvature of the sealing ball. The inner wall of the valve body is equipped with a transparent cylinder scope. In the chemical industry, when performing vacuum operations on containers containing liquid, this novel design is set within the vacuum pipeline to prevent the liquid inside the container from entering the pipeline or from flowing back from the pipeline.