The Tukad Badung Watershed is densely populated with various activities such as markets, workshops, cottages, industries, and dyeing. The waste from these activities may be the source of metals entering the Tukad Badung River will end at the estuary, which will lead to the accumulation of various discharges from the Tukad Badung watershed in the estuary. The purpose of this study where to determine Pb and Cd contents in water, fish, and sediment and their bioavailability in the sediments at the Tukad Badung estuary. The metal species of Pb and Cd in the sediment were carried out by serial extraction, and the metal content was measured using AAS. The average contents of Pb and Cd in the water is 0,3593-0,4748 mg/L and 0,1698-3709 mg/L, and in fish is 11,6966-16,4734 mg/Kg and 8,2412-13,6261 mg/Kg respectively. Based on the regulation of the Governer of Bali No. 16 of 2016 concerning the quality standard of heavy metal contents in water bodies, those metal contents have exceeded the threshold of 0.03 mg/L for Pb and 0.01 mg/L for Cd. The metal content of Pb in tilapia fish has exceeded the threshold in SNI (2009), 0.3 mg/kg, and the FAO/WHO (2004) quality standard of 0.03 mg/kg. The content of Cd in the fish has also exceeded the quality standard, which is 0.01 mg/Kg. The total contents of Pb and Cd in the sediment are 75,8229-94,2104 mg/Kg and 48,1119-54,0053 mg/Kg, respectively. The bioavailability of Pb metal is dominated by nonbioavailable metals (49,89-55,58%), followed by potentially bioavailable metals (17,37-28,81%), and the smallest metal is bioavailable (3,27-3,90%). The bioavailability of Cd metal is dominated by non-bioavailable metals (61,95-78,50%), followed by potentially bioavailable metals (5,37-23,81%), and the smallest metal is bioavailable (1,18-2,14%).