The International Maritime Organization issued a regulation to reduce sulphur content in ship fuel to a maximum of 0.5 wt% on January 1,2020. That is, the use of High Sulphur Fuel Oil as ship fuel must be replaced with Low Sulphur Fuel Oil. One type of LSFO can be produced as ship fuel MFO Low Sulphur is PTCF from PT. TPPI. However, PTCF viscosity value is relatively low, so a blending method with MBC from Cepu PPSDM is needed, which is a Low Sulphur Waxy Residue type residue with a high pour point value. Based on a journal review, determining the optimal blending point aims to determine the exact blending composition through the calculation of viscosity and pour point blending by refutas method and MBC:PTCF blending costs. This literature study aims to determine the effect of blending on viscosity, pour points, and the optimal blending composition on the characteristics of MFO