Skin cancer melanoma is one of the nineteen most prevalent cancers in the world. The needs of skin protecting active ingredients in sunscreen is still high, particularly from marine materials such as sea grapes (Caulerpa sp.). This research was aimed to develop a method that could obtain extract with high in vitro SPF value and antioxidant activity. Two extraction methods (maceration and microwave-assisted extraction) with three different solvents (ethanol, distilled water [DW], and ethanol-DW 1:1) were evaluated. The in vitro SPF value was measured using spectrophotometer UV-Vis, while the antioxidant activity was determined using DPPH. All sea grape extractions yielded in green liquid with different intensity with the odor of fish and pH value showed significantly different between extraction method and variety of solvent. The extracts obtained using maceration had SPF values 0.583, 3.099; 2.911 when using ethanol, DW and ethanol-DW as a solvent, respectively. Meanwhile the MAE produced extracts with SPF values 3.807; 5.555; 4.979, respectively. The percentage inhibition of DPPH for the MAE extracts at a concentration of 106 mg/mL were 33.85%; 22.99%; 17.44%. The MAE extract showed higher in vitro SPF values as compared to the maceration extract. The antioxidant activity in the ethanolic MAE extract was higher than in other solvents but still lower than the ascorbic acid. © 2020, IPB University Department of Aquatic Product Technology. All rights reserved.