BackgroundAs the number of older people requiring care continues to increase across the globe, maintaining care workers' mental health is an important task for all countries. This study examines the association between interpersonal relationships at work and psychological distress among care workers at elder care facilities in Japan.MethodsThis study was a secondary data analysis of cross‐sectional data. There were 406 participants who were analyzed. Questions consisted of demographic variables, psychological distress, interpersonal problems in the workplace, and intention to improve interpersonal relationships. Psychological distress was evaluated using the Japanese version of the K6 scale. Factors related to psychological distress were identified by logistic regression analysis.ResultsPrevalence of psychological distress was 53.2%. Care workers experiencing interpersonal problems in the workplace were 5.95 (95% CI: 3.82–9.43) times more likely to experience psychological distress than care workers without such problems. Moreover, those who displayed an intention to improve their interpersonal relationships were 0.33 times (95% CI: 0.15–0.71) less likely to experience psychological distress than those who did not.ConclusionsThis study found there is a strong association between workplace interpersonal relationships and psychological distress among care workers at elder care facilities. Therefore, experiencing interpersonal problems in the workplace may be a risk factor for psychological distress, and displaying an intention to improve one's interpersonal relationships may attenuate psychological distress.