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Significance Actinomycetales microorganisms are a rich source of secondary metabolites, and their genomes contain many biosynthetic gene clusters for metabolites including polyketide and peptide compounds synthesized by type I polyketide synthases (PKSs) and nonribosomal peptide synthetases (NRPSs). Genes encoding Sfp-type phosphopantetheinyl transferase (PPTase), which modifies the “apo” form to “holo” form carrier protein on type I PKSs and NRPSs, were widely distributed in Actinomycetales microorganisms, which is similar to the distribution of biosynthetic gene clusters for polyketide and peptide compounds synthesized by type I PKSs and NRPSs, respectively. Some actinomycete PPTases exhibited characteristic broad-range activities against several type I PKSs and NRPSs. These PPTases will be useful for the coexpression of several biosynthetic gene clusters including type I PKSs and NRPSs., Phosphopantetheinyl transferases (PPTases) are a superfamily of essential enzymes required for the synthetic processes of many compounds including fatty acid, polyketide, and nonribosomal peptide metabolites. These enzymes activate carrier proteins in specific biosynthetic pathways via the transfer of a phosphopantetheinyl moiety to a serine residue in the conserved motif of carrier proteins. Since many Actinomycetales microorganisms produce a number of polyketide and nonribosomal peptide metabolites, the distribution of PPTase genes was investigated in these microorganisms. PPTases were found in bacterial protein databases using a hidden Markov model search with the PF01648 (4′-phosphopantetheinyl transferase superfamily) model. Actinomycetales microorganisms harbor several genes encoding AcpS-type and Sfp-type PPTases in individual genomes, many of which were associated with the biosynthetic gene cluster for polyketide or nonribosomal peptide metabolites. The properties of these PPTases were evaluated in the heterologous expression system using the biosynthetic gene clusters and genes encoding PPTases found in the present study. Sfp-type PPTases were classified into two subgroups, and although the substrate specificities of the enzymes in one subgroup were wide, the catalytic activities of enzymes in the other subgroup were low. SAV_1784 of Streptomyces avermitilis possessed the most characteristic broad-range activity against several type I polyketide synthases and nonribosomal peptide synthetases.