Abstract: The invention relates to the field of diagnosing steatohepatitis, in particular alcoholic steatohepatitis. By following studies on a cohort of nearly 200 patients, the inventors showed that four or five specific, readily available markers, when combined in a function, make it possible, by themselves, to highly accurately diagnose steatohepatitis at the early stages of the disease, when the subject is still asymptomatic. In particular, the invention relates to a non-invasive, highly performant method of diagnosing steatohepatitis in a subject, which combines in a function the values of the age, the blood concentration of cytokeratin 18 and at least two of: the body mass index, the blood concentration of ?-2-macroglobulin and a data representative of liver stiffness as obtained by an ex vivo imaging technique. The method of the invention makes it possible to identify asymptomatic patients that may then benefit from potential therapeutics and/or be motivated to reduce alcohol consumption.