Prior research suggests that migrating to the United States (US) can negatively affect the diets and health of immigrants. There is limited information on how relocating to the US affects the diets of Black-identifying immigrants. To address this gap, this study examined differences in nutrient intake and diet quality among non-Hispanic Black adults by place of birth and length of time in the US. Cross-sectional data from the National Health and Nutrition Examination Survey (2005–2016) were analyzed. Approximately 6508 non-Hispanic Black adults were categorized into three groups: foreign-born (FB) living in the US <10 years (n = 167), FB living in the US ≥ 10 years (n = 493), and US-born (n = 5848). Multivariable-adjusted logistic and linear regression models were evaluated to identify differences in nutrient intake and diet quality (as measured by the Healthy Eating Index (HEI) of 2015) across the three groups when controlling for socio-demographics. Compared to US-born adults, both FB groups had significantly higher HEI-2015 scores and higher odds of meeting dietary recommendations for several nutrients: saturated fat, sodium, and cholesterol. There were no differences in nutrient intake between the two FB groups; however, FB (<10 years) adults had better diet quality than FB (≥10 years) ones. Place of birth and length of time in the US were associated with dietary intake among non-Hispanic Black adults. More research is needed to improve understanding of dietary acculturation among Black-identifying immigrants in the US.