In this paper, the mixing performance of a Liquefied Petroleum Gas tank with splash mixer has been investigated for three cases by computational fluid dynamics. It has been found that the view of circulation pump capacity varying of 240m3/h and 350m3/h, they show also a little bit disproportion initially but come to be uniform as time has passed. As circulation pump capacity increases, it shows little disproportion and improved flow distribution. As a result of the standard deviation toward concentration, all case shows the tendency of being stable after 200,000 seconds although their deviation are some large initially. And also, its mixture rate in case of 350m3/h is come to be stable faster slightly than 240m3/h. In conclusion of our simulation results, they can show good performance in all case respectively.