Grounded in the theory of social determinants of health, this study clarifies the relationship between social factors and health disparities in the United States. Health disparities as observed in self-rated health (SRH) status were examined across four different ethnic groups of White, Black, Hispanic, and Asian Americans. It further evaluated and compared the social determinants that account for variations in SRH status among these groups. Results from a national sample (HINTS-5 2018) showed a series of significant discrepancies in SRH among the four ethnic groups. In addition, Blacks rated their overall patient-provider communication higher than the other three groups; however, Asians reported lower ratings than the other three groups on all seven measurement items of patient-provider communication. Furthermore, findings underscored the important role of patient-provider communication as a social determinant in predicting SRH among White and Black populations, but not among Asian and Hispanic counterparts. Finally, findings suggested that social support, demographic characteristics (age, gender, and marital status), and socioeconomic status (education, occupation, and household income) influence SRH differently for the four ethnic groups. Important research and intervention implications are discussed, especially for better understanding of differences in effects of patient-provider communication on SRH by race/ethnicity.