The current study aimed to evaluate the effect of banana waste biochar on the physiological traits and growth of paspalum vaginatum under three water treatments (100%, 80%, and 60% of the water holding capacity (WHC) of the soil). A plastic pot experiment was done for the germination of paspalum vaginatum.. The treatments were the addition of compost, banana waste biochar, or banana waste biochar and compost combination to the soil. The findings revealed that banana waste biochar had an important impacts on all traits under various water supply conditions. The photon yield of PSII of control treatment at three water regimes had the lowest response compared to amended treatments. Changes were observed in chlorophyll pigment among different treatments.