To examine the association of race and ethnicity groups with self-reported racial/ethnic discrimination in patient-provider interactions during the diagnosis and treatment for breast cancer. We analyzed data from the Pathways Study, a prospective cohort of women diagnosed with breast cancer from 2006-2013 in the Kaiser Permanente Northern California Health Care System. Racial/ethnic discrimination in patient-provider interactions was assessed with two questions from the Interpersonal Processes of Care survey at baseline and 6-months and 24-months post-diagnosis. Logistic regression was performed to compare women who self-identified as racial or ethnic minorities with Non-Hispanic White (NHW) women. Covariates included age at diagnosis, country of origin, education level, income, marital status, and medical provider's race/ethnicity. Our sample included 1836 participants: 1350 NHW women and 486 women (87 Black, 208 Asian American, 153 Hispanic, 38 American Indian/Alaskan Native/Pacific Islander [AIANPI]) from racial or ethnic minority groups. In multivariate analysis, minority women were more likely to report racial/ethnic discrimination in patient-provider interactions than NHW women (adjusted odds ratio [aOR]: 4.73; 95% confidence interval [CI] 3.45-6.50). Specifically, Black women were most likely to self-report racial/ethnic discrimination in patient-provider interactions (aOR: 9.65; 95% CI 5.92-15.70), followed by Asian (aOR: 5.39; 95% CI 3.46-8.40), Hispanic (aOR: 2.55; 95% CI 1.54-4.14), and AIANPI (aOR: 1.74; 95% CI 0.58-4.25) women, compared with NHW women. Racial/ethnic discrimination was more likely self-reported from minority women diagnosed with breast cancer. Additional studies are needed to understand the mechanisms and impact of racial/ethnic discrimination in patient-provider interactions on disparities.