Oil palm is the highest oil yield crop among other oil seed crops. Due to the high global demand, large areas are planted with palm oil trees in Malaysia. Accurate information on the biomass and carbon stored in oil palm trees can describe the condition of the ecosystems to support oil palm management and conservation of oil palm resources. Biomass of oil palm trees is estimated to justify the conversion of forest to oil palm cultivation. Accurate mapping of the extent of oil palm plantations is an important first step to estimate its biomass. In this study multi- sensor satellite data combining ALOS PALSAR 2 (Phased Array type L-band Synthetic Aperture Radar), Sentinel C and Landsat Thematic Mapper (TM) were used to delineate oil palm from other land use/and cover types in Peninsular Malaysia. The second objective of this study was to classify different age of oil palm trees. The third objective of this study was to estimate the AGB according to different age class of oil palm.