The invasion of Fall Armyworm (FAW) Spodoptera frugiperda has had a significant impact on various industries in Australia. FAW infestations have led to yield losses, decreased crop quality and crop failures in maize, sorghum, sweet corn, cereals, and other key agricultural crops. In response to the threat posed by Fall Armyworm (FAW), research has explored the efficacy of endemic insect pathogens as biopesticides. Laboratory bioassays and field trials were conducted to assess the effectiveness of endemic nuclear polyhedrosis viruses (NPVs) and the fungus Metarhizium rileyi against FAW. While NPV isolates generally exhibited lower mortality in 2nd instar larvae compared to the commercial virus product Fawligen, they showed promise in larger larvae, indicating potential for controlling older instars. Additional NPVs collected from FAW and other Spodopteran hosts await testing, suggesting avenues for further research. Similarly, trials with M. rileyi isolates demonstrated promising results, with select isolates showing effectiveness comparable to chlorantraniliprole in reducing FAW larvae numbers. Field trials in sweet corn revealed significant reductions in FAW populations with the application of endemic M. rileyi, positioning it as a promising biopesticide for FAW management in Australia. These findings underscore the potential of endemic insect pathogens as sustainable alternatives for FAW control, warranting continued investigation and development.