The liquid carrier propulsion and utilization system is mainly used to adjust the mixing ratio of the engine and propellant, enabling the engine to work in a high specific impulse state for a long time, and to provide sufficient impulse by filling the propellant, reducing the dead weight of the propellant, thereby improving the carrier’s carrying capacity. It is an overall technology involving the control, power, and measurement systems of the carrier. Currently, research mainly focuses on the synchronous depletion of two propellants, lacking analysis of the dynamic mixing ratio during flight, and the disturbances considered are generally constant flow disturbances. The simultaneous flow and margin are generally known by default. In response to the above problems, this article first fully considers the sloshing characteristics of liquid propellants and constructs a complete and realistic propellant consumption and control process. Next, establish residual propulsion dose estimation models based on liquid level and liquid level flow rate, and design filtering algorithms to improve the accuracy of residual estimation. Finally, design a propellant utilization algorithm that considers both final margin control and consumption process flow control.