Abstract: LNG has the high calorific value and low emission characteristics as ship fuel, so it is one of the most feasible method to solve the emission problem. With the limit emission rules carryed out, more and more owners tend to add the LNG-ready design in the new shipbuilding stage, therefore the ship will be flexible to be retrofitted to dual-fuel power directly. This paper shows the basic design flow and key technical routes about LNG-ready design on large ocean products oil tanker, based on the real ship LNG-ready design project delivered by Dalian Shipbuilding Industry Co.，Ltd., which will be a reference for domestic and foreign ship design industry.