As a drilling operation proceeds deeper and deeper, drilling temperature tends to increase rapidly. This increase influences the drilling mud rheological properties negatively. The negative effect includes severe decrease of mud viscosity and gel strength, which makes many of mud additives not functional at high temperature. On the other hand, efforts are needed to be taken seriously against the large amount of lignocellulosic waste from oil palm industry. Recycling the unwanted materials into a valuable product is an industrial and environmental challenge which necessitates the need of better waste management. Therefore, this study investigates the possibility of lignin graft copolymer (LGC) as a potential hydrocarbon drilling