The purification process of sugarcane juice in a sugar factory mostly uses sulphitation process, separating clear juice from dirty juice using a sedimentation system. Impurities on the processing of sugarcane juice will further cause difficulties, the formation of color, an increase in viscosity, and reducing sugar recovery. Membrane purification technology is offered to overcome these problems. This study aims to determine the effect of chitosan and acetic acid on the performance of chitosan membranes in the clearance of sugarcane juice and to find the best concentration of chitosan and acetic acid for the purification process of sugarcane juice. The filtration process was performed by using the chitosan membrane to process a clear sugarcane juice sample from the pretreatment result, which is assumed as clear juice product from sulphitation process in sugar factory. The results showed that (1) the result of pretreatment had the value from TSS (Total Soluble Solids) of 15.4%; turbidity of 82.33 NTU; and the ICUMSA (International Commission for Uniform Methods of Sugar Analysis) colour of 14970.02 IU. (2) After filtration using membrane, better quality of pretreatment clear sugarcane juice is obtained, characterized by increasing chitosan concentration at each acetic acid level, rejection value of TSS, turbidity, and ICUMSA colour. (3) The best treatment result based on Zeleny multiple attribute method is found in chitosan membrane with concentration of 4%, acetic acid concentration of 1.5% to inject TSS until reaching 12.64%, ICUMSA until reaching 9.89%, and rejection of turbidity until reaching 63.61%. Higher chitosan concentration caused small pore size of the membrane.