The frequencies of alleles in the HLA‐DRB1*01 family were determined in each of five US populations from a database of 82,979 individuals. Individuals typed as DR1 (or DRB1*01) comprised between 7.6%–21.3% of the individuals in each population group. Fifty‐nine DR1 individuals were randomly selected from each group and subjected to high‐resolution DNA typing by polymerase chain reaction using sequence‐specific oligonucleotide probes. DRB1*0101 was the most common allele in the Caucasian, Asian/Pacific Islander, and Native American groups while the DRB1*0102 allele was found in the majority of African Americans and Hispanics. DRB1*0103 was present at a similar frequency in all populations. DRB1*0104, DRB1*0105, and DRB1*0106 alleles were not observed.