The amino acid sequence of the rat 60S ribosomal subunit protein L11 was deduced from the sequence of nucleotides in a recombinant cDNA. Ribosomal protein L11 has 178 amino acids and a molecular weight of 20,239. Hybridization of the cDNA to digests of nuclear DNA suggests that there are 6-8 copies of the L11 gene. The mRNA for the protein is about 800 nucleotides in length. Rat L11 is homologous to ribosomal proteins from other eukaryotes and is related to the L5 family of proteins from eubacterial and archaebacterial ribosomes.