because the NR latex has a colloidal characteristic which obstruct the penetration of light beam. Thus, digestion of NR latex before the determination of phosphate in NR latex is a crucial step. Digestion process is a procedure for destroying the rubber constituents until receiving clear solution. It uses energy such as heat from UV light, microwave and thermoreactoror uses chemical reagents such as acids or uses a combination of the two methods [5,6]. In our previous studies, environmental [7,8,9] and pharmaceutical samples [10] containing phosphorus were determined by using ammonium persulphate or potassium persulphate as oxidizing agentor used in conjunction with acid such as perchloric acid or sulfuric acid and used UV light for providing energy. For NR latex sample [11], previous study used Kjeldahl technique as digestion procedure which used concentrated sulfuric acid and nitric together with high pressure and temperature.