Abstract:Abstract: [Objective] Based on the molecular diversity information, seven actinomycete-selective culture media and isolation conditions were modified to isolate and cultivate diverse rare actinomycetes from Hymeniacidon perlevis. [Methods] Modified, selective cultivation and enrichment media were used, with the addition of an elemental solution of simulating the elemental composition of marine sponge H. perlevis. Restriction Fragment Length Polymorphism (RFLP) analysis of 16S rDNA sequence was used to reveal the diversity of culturable rare actinomycetes. [Results] A total of 59 actinomycete strains were isolated from the marine sponge H. perlevis. A total of 27 representative actinomycetes were selected according to their morphological feature, color and pigments. They gave 15 different RFLP patterns after digesting their PCR products of 16s rDNA with Hha I. The results showed that these isolates belonged to 10 genera: Streptomyces, Nocardiopsis, Micromonospora, Cellulosimicrobium, Gordonia, Nocardia, Prauseria, Pseudonocardia, Saccharomonospora and Microbacterium. [Conclusion] The modified isolation media and selective cultivation procedures are highly effective in the recovery of culturable actinomycetes from the marine sponge H. perlevis, resulting in the highest diversity of culturable rare actinomycetes from any sponges.