Cigarette butts, one of the most ubiquitous forms of garbage in the world, need to be recycled because their toxicity can kill saltwater and freshwater fish. In this study, the cigarette butts are applied as corrosion inhibitors for N80 steel at 90 degrees C in hydrochloric acid. Weight loss and electrochemical techniques are used to evaluate the corrosion inhibitive effect of cigarette butt water extracts. Results show that the inhibition efficiencies arrive at 94.6% and 91.7% in 10% and 15% (wt %) HCl solution, respectively, by adding 5% (wt %) inhibitor. In 20% HCl solution, they show a maximum inhibition efficiency of 88.4% by adding 10% inhibitor.