Abstract: Based on the operation process, this paper presents a simple lab method for evaluating the oil-based cement slurry for water shutoff. This paper comprehensively evaluates the mixing, hydration and core experiments of the slurry and primarily explores its hydration mechanism and selectivity. The study indicates that the developed oil-based cement slurry is with higher post-hydration compressed strength and better selectivity, but with poor injectivity. It is suggested that the slurry had better be injected together with other water shutoff agents with good injectivity.