Primary biliary cholangitis (PBC) is often overlapping with other autoimmune conditions, including systemic lupus erythematosus (SLE). Since the concomitant PBC and SLE are rare, the impacts of SLE on the response and prognosis in ursodeoxycholic acid (UDCA)-treated patients with PBC remain unclear.A PBC database of 769 patients at West China hospital was used to identify 26 patients with concomitant PBC and SLE. The clinical and biochemical characteristics of these patients were collected and analyzed. Propensity score matching was used to compensate for the differences in age, total bilirubin, and alkaline phosphatase. The biochemical responses and prognoses were compared between the patients with and without concomitant SLE.The female-to-male ratio was 25:1 in the PBC patients with concomitant SLE. Compared with the group with PBC alone, the median hemoglobin and albumin values in the PBC-SLE group at the time of diagnosis of PBC were lower (both P < 0.05). After treatment, the group with PBC alone showed lower alanine aminotransferase and glutamyltransferase values and aspartate aminotransferase/platelet ratio indices at the final visit (all P < 0.05). The Kaplan-Meier estimate showed that the adverse event-free survival did not differ between the patients with and without concomitant SLE (P = 0.564).The results of this retrospective, single-center study suggested that the concomitant SLE status might have a negative impact on the biochemical responses to the treatment, while the effect of concomitant SLE on PBC progression remains to be further defined.Key Points• The prevalence of SLE in the PBC population being in a large PBC cohort was as low as 3.4%.• Compared with PBC-SLE group, the group with PBC alone showed lower alanine aminotransferase and glutamyltransferase values and aspartate aminotransferase/platelet ratio indices at the final visit, indicating that the concomitant SLE may have a negative impact on the biochemical responses to the treatment of PBC.