Endurance sports are classified as activity which puts very high stress on psychological and physical profile of an athlete. Expectations are very high, so in today`s sports perople are looking for a way to enhance sports performance and results. Nutrition is a key to success and a base of all, but by research we came to a conclusion that sports supplements make a significant difference in sports success. Sports supplements have become essential part in sports nutrition and life in general. Sports supplements in endurance sports are numerous, and some of the most frequent ones are caffeine, nitrates, antioxidants, omega-3 fatty acids, and carbohydrates. Availability of supplements today is an advantage but precaution is needed beacuse of the possible side effects and untested substances which could be labelled as doping. The goal of this systematic review of litterature is to represent the newest discoveries about the effectiveness of sports supplements on endurance and sports performance. Systematic review of literature is based on studies published between 2016. i 2021. Total number of studies that correspond to the criteria in this systematic review is 37. By analysing all the studies, conclusion is that ergogenic effect is made by consuming desired dose and time of consumption (acute or chronic), also effect is similar in men and women.