Introduction: The production of tofu produces tofu liquid as a wastewater containing isoflavones. Isoflavones can be used as nutraceuticals. The excretion of nutraceuticals in the body mainly occurs in the kidneys, so it is necessary to know their safety for consumption. This study is to determine the safety of tofu wastewater as nutraceutical for the kidney of Wistar Rat (Rattus norvegicus). Methods: This study used a sample of 48 Wistar Rats divided into 6 groups: control group (K), dose 1 which given 6ml/KgBW group (D1), dose 2 which given 12ml/KgBW group (D2), dose 3 which given 18ml/KgBW group (D3), satellite dose 1 group (S1), and satellite dose 3 group (S3). Tofu wastewater was given out for 28 days and an additional 14 days without treatment in the satellite group. Kidney histopathological was observed using a microscope with a magnification of 400x. Results: The Kruskall-wallis test showed there was a significant differences in renal histopathological damage in each groups (p=0,025). The Mann-Whitney test showed there was significant differences in the dose 1 (D1) group, dose 2 (D2) group, dose 3 (D3) group, satellite dose 1 (S1) group, and satellite dose 3 (S3) group toward the control group (K). Conclusion: Tofu wastewater with multilevel doses can cause toxic effect in the form of kidney histopathological damage, however there is a healing process or reversible effect in the satellite group.