Marine environments are rich sources of diverse microbial life, including actinomycetes with potential for the synthesis of bioactive compounds. In this study, marine water samples were collected from Ras Sedr, Egypt, and actinomycetes were isolated using standard cultivation techniques. Small-scale fermentations were conducted, and crude extracts were obtained from the selected actinomycete isolates. Antimicrobial screening was conducted to assess the inhibitory activity of the crude extracts versus a panel of bacterial strains. The most potent strain, designated as Streptomyces sp. RSE, was selected based on its remarkable antimicrobial activity. Morphological and genetic identification methods were employed to characterize the strain. Furthermore, gas chromatography (GC) analysis was utilized to identify the bioactive metabolites present in the crude extract. Among the identified compounds, 3,5-Dimethyl-1,3,4-hexanetriol was determined to be a major constituent. The biological activities of this extract from Streptomyces sp. RSE were evaluated, focusing on antioxidant and anticancer properties. The extract exhibited significant antioxidant activity, as demonstrated by various assays. Additionally, its anticancer potential was investigated against selected cancer cell lines, revealing promising cytotoxic effects. This study highlights the potential of marine actinomycetes from Ras Sedr as valuable sources of bioactive compounds.