Human placental extract (HPE) is a traditional medicine that has been used for the symptomatic treatment of liver disease without any verifying clinical evidence. This study aimed to evaluate the efficacy and safety of HPE in patients with alcoholic or nonalcoholic steatohepatitis (ASH or NASH). We designed this clinical trial as a multicenter, open-label, randomized, comparative noninferiority study to improve the reliability of analyses. The enrollment criteria were limited to ASH or NASH patients with serum alanine aminotransferase (ALT) 1.5-fold higher than the normal level. Patients in the control group were treated with a commercially available mixture of liver extract and flavin adenine dinucleotide (LE–FAD). Intention-to-treat (ITT) analysis was applied to 194 patients, and per-protocol (PP) analysis was available for 154 patients. The rate of primary goal achievement of treatment efficacy was arbitrarily defined as 20% or greater improvement in ALT level compared with the pretreatment level and did not differ significantly between the HPE and control groups [62.9% (44/70) vs. 48.8% (41/84); p =0.0772]. ITT and modified ITT analysis showed results similar to those of PP analysis. Adverse drug reactions (ADRs) of minimal to moderate degree occurred in 3.1% of patients. The ADR and treatment compliance rates were similar in both groups. In conclusion, the clinical value of HPE in the treatment of ASH and NASH is equivalent to that of LE–FAD.