The cDNA clones for two members of a novel protein kinase family were isolated and sequenced. These protein‐kinase‐C‐related kinases, PRK1 and PRK2, display extensive identity to each other, revealing non‐kinase domain similar regions, HR1 and HR2. HR1 contains a motif repeated three times (HR1a–c), while HR2 shows similarity to the amino‐terminal sequence of protein‐kinase‐C ɛ and η isotypes. Both PRK1 and PRK2, expressed in COS 1 cells, are autophosphorylated in immunoprecipitates, indicating intrinsic kinase activity. PRK1 and PRK2, as well as a third member of this family, PRK3, show distinct patterns of expression in adult tissues.