THIS WORK is aimed to assess the antibiosis efficacy of marine thermophilic actinomycetes isolated from raw marine habitat and identify the most antibiosis effective isolate. Variable thermophilic actinomycete strains were isolated from 14 marine sediment samples at Burj Al Arab, El-Agamy salinases and Cairo-Alex route Alexandria, Egypt. The isolated strains were purified and screened for their antibiosis activities against various targets of human pathogenic bacteria and fungi. Actinomycete isolate, characterized by highest broad-spectrum antagonism, was selected and identified based on morphological, cultural, physiological and biochemical characteristics. Total cell hydrolysate analysis, Genomic DNA extraction and 16S rRNA sequencing were also characterized. Among the purified 135 marine thermophilic actinomycete isolates, twenty strains showed detectable antagonistic activities against test pathogens. Based on identification collected data, it was suggested that the most potent undertreat isolate is belonging to actinomycete genus Saccharomonospora. Molecular studies revealed that it was highly related to Saccharomonospora viridis (100%). As a result, it was designated as Saccharomonospora viridis AHK190.