The power of two-stroke engine is influenced by the scavenging efficiency. Matching in-cylinder swirl ratio for injection system is indispensable. It is important to get low scavenging pressure to decrease mechanical power loss. This paper describes the effect of the scavenging ports configuration to the swirl ratio, the scavenging efficiency and the scavenging pressure, in case of uniflow scavenging two-stroke diesel engine that has four exhaust valves and the cylinder liner with scavenging ports. Especially we researched the relative advantages and disadvantages of shape factors using case-study by in-cylinder computational fluid dynamics simulation.