The production of drinking water from raw water sources involves coagulant use at a coagulation/flocculation stage, to remove turbidity in the form of suspended and colloidal material. Many coagulants and flocculants are widely used in conventional water treatment processes. Aluminum and ferric salts can be classified as inorganic coagulants while polyacryl amide derivatives and polyethylene imine falls in the category of synthetic organic polymers. Currently, the conventional water treatment processes use inorganic coagulants such as aluminum polychloride and aluminum sulfate for the coagulation/flocculation processes. However, studies show that the usage of the inorganic coagulant causes serious damage to the human health. In the current study, the effectiveness of Pullulan and extract of Senna Alata as bio coagulant for water treatment was explored as an alternative material for the conventional coagulant for water treatment. Senna alata leaves were extracted by using the water extraction method. The bio coagulant of Pullulan and Senna Alata extract s were prepared at different mixing ratios. The effectiveness of bio coagulant was determined through assessments on the treated water quality in terms of turbidity, pH, and dissolved oxygen. The effectiveness of the Pullulan and Senna Alata extract as bio coagulant for water treatment was shown to be more efficient compared to treatment using conventional chemicals.