Abstract: Micromonospora is one of actinomycetes belonging to Gram-positive bacteria. It was found both inside plant tissues and outside tissues as free-living bacteria. The objectives of this study were determined the distribution of Micromonospora in sugar cane tissues; root, leave and stem which obtained from 5 provinces in Thailand. The results showed that 147 endophytic actinomycetes were isolated. Most endophytic actinomycetes were found in plant root due to high root exudates in rhizosphere whereas the localization of most Micromonospora were found in plant stem. Among these, thirty-four isolates has identified as Micromonospora by using morphological character and meso-diaminopimelic acid. They were grouped into 5 different groups based on color of substrate mycelium. In this way, most of them belong to Gr. 1 with 10 members. The representative isolates of each group were analyzed 16S rDNA sequence and construct phylogenetic tree. The phylogenetic tree showed Gr. 1 to Gr. 5 were closed relationship to Micromonospora coriariae, M. brigensis, M. humi, M. rifamycinica and M. saelicesensis, respectively. This is the first descriptions of the presence of Micromonospora inside the sugar cane tissue.