The increasing emphasis on sustainable agricultural practices in the Philippines has intensified the search for eco-friendly and cost-efficient pest control alternatives. Biopesticides, particularly those based on entomopathogenic fungi like B. bassiana, offer a promising solution. This study investigates the enzymatic activity and mass production potential of three native B. bassiana isolates (CD3, CD11, and DSMA1) cultured on readily available agricultural byproducts—banana leaves, corn husks, Pinus kesiya (pine) sawdust, and rice. Enzyme assays measured the isolates' proteolytic, lipolytic, chitinolytic, amylolytic, and ligninolytic activities to assess their substrate compatibility and potential for virulence. Among the three, isolate CD3 exhibited the highest spore yield and was most active in proteolysis and amylolysis, indicating strong degradation and nutrient acquisition abilities. DSMA1 showed the greatest chitinolytic activity, while CD11 was dominant in lipolytic activity. Of the substrates tested, rice supported the highest spore production across all isolates, followed by corn husks and banana leaves. Pine sawdust, however, proved unsuitable due to its high lignin content, which hindered fungal growth. These findings support the use of locally sourced substrates to cultivate effective biocontrol agents. This research contributes to the development of region-specific, sustainable pest management strategies that enhance food security and reduce chemical pesticide reliance in Philippine agriculture.