Pumpkin seed (Cucurbita moshcata D.) has been reported to contain bioactive compounds and functional nutrients such as vitamin, fiber, and antioxidants. This research was aimed to produce fermented beverage made from pumpkin seeds. The fermented beverage was processed by seeds to water ratio and addition of skim milk and prepared with cultures of Lactobacillus plantarum and Streptococcus thermophilus. The combination of seeds and water were mixed with different ratios of 1:3, 1:4, and 1:5 (w/v). Skim milk were mixed with different concentrations of 5% and 10% (w/v) and fermented for 12 hours, which were then analyzed for pH, total titratable acidity, and total lactic acid bacteria. The result showed that based on these parameters, the best formulations were the seeds to water ratio 1:3 and 10% skim milk. The best formulation was used to find the best cultures ratio. The combination of Streptococcus thermophilus and Lactobacillus plantarum with different ratios of 1:1, 1:2, and 2:1 (w/v) were mixed and analyzed for pH, total titratable acidity, and total lactic acid bacteria. The result showed that based on these parameters, the best formulations were the cultures ratio of Streptococcus thermophilus and Lactobacillus plantarum, 1:1. The best formulation were analyzed for coliform test, toxicity test, proximat test, antioxidant activity, phenolic, flavonoid, and hedonic test. Pumpkin seeds based fermented beverage has a negative result for coliform test, result of toxicity test 786,90, contains 83,62% of water, 0,84% of ash, 2,30% of milk fat, 4% of protein and 9,24% of carbohydrate. Pumpkin seeds based fermented beverage also contains antioxidant activity (IC50) 291694,47±1242,60 mg/L, phenolic 643,27±13,04 mg GAE/L sampel, and flavonoid 612±7,5 mg GAE/L sampel. In conclusion, pumpkin seeds based fermented beverage was still acceptable by panelists and contains functional nutrients that good for health