New in-vitro SPF test method is based on UV (Ultra Violet) dosage cumulate responseusing Gafchromic EBT3 film. The color of film become darker (blue) with more UV dosage, and the dosage could be calculated by standard curve calibration. To test SPF value, sunscreen sample was applied on EBT3 film homogeneously by standard procedure, then the film was irradiated by UV chamber for 30 minutes. SPF value is calculated by comparing the dosages of films received with or without sunscreen.