Aim of the study is to determine the relationship between liver function and the incidence of ONF after steroid therapy in AID patients. The present study investigated 58 AID patients who had received high-dose systemic steroid therapy to determine whether a correlation exists between parameters of hepatic function and steroid-induced ONF at the precise time-point when steroid-induced ONF develops. The patients were divided into two groups on the basis of MRI findings: ONF (n = 31) and non-ONF (n = 27). The ONF group showed no increase in AST, ALT, or LDH within 4 weeks after the commencement of steroid therapy. By contrast, the non-ONF group showed an immediate and significant increase in all of these parameters. In the ONF group, hepatic steatosis and elevated triglyceride levels were also observed. Following 4 weeks of steroid therapy, there were no significant differences in biochemical data between two groups. Patients showing no immediate increase in ALT and AST in response to steroid therapy were at high risk of ONF. These findings provide important insights into the pathogenesis of steroid-induced ONF and may facilitate the development of prevention strategies in patients with AID.