For ages people have used many part of soursop tree as traditional medicine. Every part of soursop leaves has many health benefits. The leaves of soursop tree (Annona muricata Linn.) can be made into tea that has proven to be rich in antioxidant and antidiabetic properties. The tea can be made into soursop leaves kombucha by SCOBY (Symbiosis Colony of Bacteria and Yeast). This research was aimed to study the effect of kombucha fermentation to the antioxidant and antidiabetic properties of soursop leaves tea. There were two stages in this experiment, in the first stage, treatments used are the ratio of black tea and soursop leaves tea (100:0, 72:25, 50:50, 25:75, 0:100) and the amount of sugar added (7%, 9%, and 11%) In the second stage, fermentation time of selected kombucha samples were used as treatment (100:0 with 110 grams sugar, 75:25 with 110 grams sugar, and 50:50 with 70 grams sugar). The fermentation time are from day 0 until day 16th and sample taken for analysis in day 0,4,8, 12 and 16. The highest antioxidant activity are from kombucha made from 100% black tea and 110 grams sugar in day 4th with IC50 20,529±4,872 ppm and 50% black tea, 50% soursop tea with 70 grams sugar in day 4th with IC50 45,000±0,902 The highest antidiabetic activity owned by kombucha made from 100% Black Tea (110 grams sugar) with percent inhibition 92,91% and 50% black tea and 50% soursop leaves tea (70 grams sugar) with percent inhibition 92,60%. The interaction also significantly affected the total phenolic content, total flavonoid, color, pH, and total plate count of the kombucha samples.