The utility model relates to a water ballast system with immersed pipe joints, in particular to a water ballast system with pipe joints capable of being stably and quickly immersed by means of controlling the water storage capacity of ballast tanks. The water ballast system comprises a pipe joint control circuit, the ballast tanks and ballast pumps. The ballast pumps are connected with the ballast tanks by pipelines. The water ballast system has the advantages that the water ballast system is provided with the ballast tanks; self-weights of the pipe joints are controlled by means of injecting water into the ballast tanks or draining water in the ballast tanks according to a buoyancy principle, so that the pipe joints are adaptive to buoyancy of underwater positions at different depths, and can be quickly, freely and stably immersed; the immersion speed of the pipe joints is matched with descending and ascending actions of a hanger cable; load on the hanger cable is relieved; the immersion construction precision is improved, the immersion construction progress is accelerated, and the immersion construction efficiency is enhanced.