This paper presents the studies on the liquefaction of three types of oil palm biomass; empty fruit bunch (EFB) frond oil palm (FOP) tree oil palm (TOP) was investigated under subcritical water conditions in a batch reactor. Catalytic (KOH) performance and suitable biomass of temperature (250, 275 300 ๐C) and pressure (60, 88, 42 bar) on bio-oil yield. The optimum liquefaction condition of three types of biomass was found to be at subcritical condition of water at 275๐C and 60 bar, with EFB yielding the maximum bio-oil yield of 22.66 wt % followed by FOP and TOP, with optimum yield of 9.72 wt % at 300๐C and 88 bar, and 8.25 wt % at 250๐C and 42 bar , respectively.