Background: Cancer patients receiving chemotherapy face an increased risk of reactivation of chronic hepatitis B virus infection.Aim: To determine the HBV screening rate in patients receiving cancer chemotherapy in various clinical settings.Method: We identified 11,959 adult cancer patients (age ≥ 18 years) receiving parenteral chemotherapy between 2012 and 2015 within a major US hospital network, including a large university hospital, community teaching hospitals, and community oncology clinics.Result: Two thousand and forty-five patients (17.1%) were screened for either HBV surface antigen (HBsAg) or HBV core antibody (HBcAb) before chemotherapy, and 1850 patients (15.5%) had both HBsAg and HBcAb tested before chemotherapy. 8.4% were exposed to HBV, and 0.9% had chronic HBV infection (both HBsAg/HBcAb positive). Patients with hematologic tumor were more often screened than with solid tumor (55.6 vs. 8.3%, p < 0.001). Patients receiving chemotherapy with higher HBV reactivation risk had higher yet suboptimal HBV screening rate (41.1% B-depleting agents, 21.5% anthracycline, 14.9% steroid, 64.7% anti-TNF alpha and 18.6% other chemotherapy, p < 0.001). Patients with age ≥ 50 years (old 16.2% vs. young 23.9%, p < 0.001) and Asian ethnicity (Asian 13.6 vs. Caucasian 16.6%, p < 0.001) were screened less for HBV despite higher prevalence of HBV exposure (old 9.3% vs. young 4.3%, p < 0.001 and Asian 27.8% vs. Caucasian 6.4%, p < 0.001). Patients receiving chemotherapy in community oncology clinics were less screened versus community teaching hospitals or university hospital (12.7 vs. 19.1 vs. 19.7%, p < 0.001), despite similar prevalence of HBV infection. On multivariate analysis, receiving chemotherapy at a community oncology clinic [odds ratio (OR) 0.57, 95% confidence interval (CI) 0.45-0.72, p < 0.001] was independently associated with less HBV screening compared to receiving chemotherapy at a university or community teaching hospital.Conclusion: HBV screening among patients undergoing cancer chemotherapy was suboptimal and less commonly performed in community oncology clinics compared to teaching hospitals. [ABSTRACT FROM AUTHOR]