Sorghum juice can be used as raw material for producing liquid sugar. Impurity matters are one of the problems in producing liquid sugar that can affect the final product. The goal of clarification is to remove suspended and turbid particles and to allow subsequent concentration in a viable liquid sugar product using standard commercial evaporation technologies. This research aims to determine the optimum concentration of zeolite and the preheating temperature for removing impurities matters in the clarifying process. This study used a Randomized Block Design method with two factors, namely zeolite concentration factor with three levels (1.5%, 3%, 4.5%) and preheating temperature with three levels (60°C, 75°C, 90°C). The results show that the purification process with these two factors manages to clarify sorghum juice well. The best results of the purification process are obtained at 4.5% zeolite concentration and 90°C preheating temperature, with the results of remaining starch content of 0.754 ± 0.041%, protein content of 0.13 ± 0.007%, ash content of 1.198 ± 0.0028%, pH value 5 ± 0.1, turbidity of 9.14 ± 0.21 NTU, total dissolved solids 21.20 ± 0.4 Brix, density of 1.0708 ± 0.0026 gr / ml, brightness (L*) of 46.239 ± 1.16, redness (a*) of -0.694 ± 0.22, and yellowness (b*) of 25.91 ± 0.48.