Bakhri, Syaiful2019-01-082019-01-082019-01-09978-979-792-865-0wahyu sari yenihttp://repository.unri.ac.id/handle/123456789/9516Parameter water quality of receiving water bodies to discharge liquid waste rubber industry which produces crumb rubber PT. X consists of content, BOD, COD, TSS, ammonia, total N and pH. This study aims to determine the value of Lethal Concentrate (LC50) of water from effluent receiving water bodies crumb rubber mill effluent on fish guppy. This type of research is experimental acute toxicity test methods such as static toxicity tests of the toxicity tests on the test organisms are treated with a series of concentrations of toxic materials without water replacement test using the design of completely randomized design (CRD). The results of this study is the LC50 value of water from receiving water bodies to discharge liquid waste crumb rubber factory PT. X amounted to 89.14%. The conclusion of this study is, water from receiving water bodies to discharge liquid waste crumb rubber industry will result in the death of more than 50 percent of the fish guppy despite the addition of distilled water (dilution) as much as 10.86 percent of the water volume of the receiving water body liquid waste disposal plant rubber crumb PT. X.enToxicityeffluentsLC50Article