Nanomaterials were highly inspired in the field of nanotechnology especially bio synthesized silver nanoparticles (AgNPs) have effectively attracted worldwide that helps to improve in the field of medical science and human health. Actinabacteria mediated nanoparticle were widely used to control insect pests, treatment of antibiotic resistant bacteria, cancer and other diseases due to their potential pharmacological properties compared with other chemical drugs. The present investigation an entomopathogenic actinobacteria Actinokineospora fastidiosa was isolated and synthesis of AgNPs and tested their mosquito larvicidal, antibacterial and anticancer activity. Moreover, the outcome of biosynthesized AgNPs was characterized by UV-visible spectroscopy, X-ray Diffraction (XRD), Fourier transforms infrared spectroscopy (FT-IR), Transmission electron microscope (TEM), scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDX) and zeta potential analysis. The characterized AgNPs showed a potent larvicidal activity against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus the obtained LC50 values is 9.86 ppm, 8.50 ppm and 8.29 ppm respectively. However, at 25 ppm concentration, AgNPs showed highest ovicidal activity (100 %, 100 % and 97.77 % against A. aegypti, A. stephensi and C. quinquefasciatus respectively) and oviposition deterrence activity was 100 %, 100 % and 98.66 % were achieved against A. aegypti, A. stephensi and C. quinquefasciatus respectively. The enzymes of α, β esterase and Glutathione-S-transferase level were increased due to detoxification process against AgNPs. The histopathological results of AgNPs showed series damage in epithelial cells and brush border cell of mosquito larval gut. In addition, actinobacterial mediated AgNPs was tested against different human pathogenic bacteria. The obtained results showed biosynthesized AgNPs revealed remarkable antibacterial activity against all tested pathogens. The lowest mortality was observed on non-target organisms of Artemia salina at highest concentration of AgNPs. Finally, in vitro toxicity study showed that biosynthesized AgNPs potential anticancer activity and induced reactive oxygen species (ROS) production in human cervical cancer (HeLa) cell line at an inhibitory concentration (IC50) range 42.37 μg/mL. Therefore, it can be concluded that biosynthesized AgNPs using a novel stains Actinokineospora fastidiosa potentially influenced the vector mosquito and bacterial diseases management and pharmacological applications in eco-friendly manner.