Abstract: Salmo trutta macrostigma is a freshwater fish species, which is very important in terms of biodiversity end economic utilization. The present study aims to study the reoccurrence and conservation of S. t. macrostigma in Lake Sapanca Basin (Sakarya, Turkey) during 2006. It has only once been reported from Lake Sapanca Basin in 1943. This fish species was not found until 2006, when a single specimen was found during routine and follow-up surveys. The measural and meristic characters of the specimens were similar to those reported elsewhere for the species. Conservation needs and threats for the species are discussed.