ABSTRAKAnggur laut (Caulerpa sp.) merupakan salah satu jenis alga hijau yang tumbuh di beberapa wilayah Indonesia, diantaranya Pulau Sapudi, Madura. Penelitian ini bertujuan untuk mengetahui aktivitas antioksidan pada anggur laut (Caulerpa sp.) asal Pulau Sapudi Madura dengan metode pengeringan yang berbeda. Metode yang digunakan dalam penelitian ini, yaitu perhitungan rendemen, analisis proksimat, analisis fitokimia dan analisis antioksidan menggunakan DPPH (2,2-diphenyil-1-picrylhydrazyl). Hasil dari penelitian menunjukkan anggur laut dengan metode pengeringan sinar matahari memiliki randemen 11,62%, sedangkan sampel anggur laut dengan pengeringan angin memiliki randemen sebesar 7,87%. Hasil analisis proksimat sampel kering menunjukkan bahwa anggur laut dengan pengeringan sinar matahari memiliki kadar air 10,33%, kadar abu 27,62%, kadar lemak 0,07%, kadar protein 0,87%, kadar serat 0,20% dan kadar karbohidrat 60,92%. Sampel anggur laut dengan pengeringan angin memiliki kandungan kadar air 12,11%, kadar abu 38,15%, kadar lemak 0,13%, kadar protein 0,87%, kadar serat 0,25% dan kadar karbohidrat 48,49%. Ekstrak kasar sampel anggur laut dengan pengeringan sinar matahari menunjukkan adanya kandungan alkaloid dan saponin. Sementara ekstrak kasar sampel anggur laut dengan pengeringan angin menunjukkan adanya kandungan saponin dan fenol hidrokuinon. Hasil analisis antioksidan dari perbandingan kuarsetin diperoleh nilai 2,640 ppm. Aktivitas antioksidan dari sampel kering sinar matahari memiliki nilai IC50 sebesar 491,961 ppm yang berarti aktivitas antioksidannya sangat lemah. Sementara sampel kering angin memiliki nilai IC50 sebesar 199,932 ppm yang artinya aktivitas antioksidannya lemahKata Kunci: Anggur laut (Caulerpa sp.), antioksidan, pengeringan berbedaABSTRACTSea grapes (Caulerpa sp.) are a type of green algae that grows in several regions of Indonesia, including Sapudi Island, Madura. This research aims to determine the antioxidant activity of sea grapes (Caulerpa sp.) from Sapudi Island, Madura using different drying methods. The methods used in this research are yield calculation, proximate analysis, phytochemical analysis and antioxidant analysis using DPPH (2,2-diphenyl-1-picrylhydrazyl). The results of the research showed that sea grapes using the sun drying method had a yield of 11.62%, while sea grape samples using wind drying had a yield of 7.87%. The results of proximate analysis of dried samples showed that sun-dried sea grapes had a water content of 10.33%, ash content of 27.62%, fat content of 0.07%, protein content of 0.87%, fiber content of 0.20% and carbohydrates 60.92%. Wind-dried sea grape samples had a water content of 12.11%, ash content of 38.15%, fat content of 0.13%, protein content of 0.87%, fiber content of 0.25% and carbohydrate content of 48.49%. Sun-drying crude extracts of sea grape samples showed the presence of alkaloids and saponins. Meanwhile, wind-drying crude extracts of sea grape samples showed the presence of saponins and phenol hydroquinone. The results of antioxidant analysis from the comparison of quarcetin obtained a value of 2,640 ppm. The antioxidant activity of the sun-dried samples had an IC50 value of 491.961 ppm, which means the antioxidant activity was very weak. Meanwhile, the wind-dried sample had an IC50 value of 199.932 ppm, which means the antioxidant activity was weak.Keywords: Sea Grapes (Caulerpa sp.), antioxidant, different drying