Abstract Background Infectious diseases prompted by micro-organisms such as fungi, parasites, or microbes, have infuenced many countries’ public health causing death. Scientists declared that metal oxide composites have various advan‑ tages in the medical feld such as the antimicrobial feature has freshly been revealed as well as its role in suppressing mosquito population. Methods In this work silver doped zinc oxide nanorods (Ag/ZnO NRs, 10 wt.%) were prepared by simple chemical route, and their microstructural characteristics were investigated by XRD, EDX, SEM, and TEM techniques. The antimi‑ crobial, larvicidal, and ovicidal of the synthesized nanocomposites were examined. Results The synthesized nanocomposite exhibited binary phase of crystallite size 112 nm was calculated from Wil‑ liamson-Hall method. EDX spectrum revealed the purity of the composite consists of Zn, O, and Ag elements. The SEM and TEM micrographs showed the particles in nanorods with high density on the surface. The energy gap (Eg) was evaluated from the UV–Vis absorbance in the range from 2.90 − 3.08 eV inside the visible spectrum. The anti‑ microbial activity of the nanorods was examined against Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) with inhibition zones 10.5 and 14.5 mm, respectively. Whereas gram-negative bacteria (Escherichia coli, Salmonella Typhimurium, and Pseudomonas aeruginosa) were 14 and 17 mm, respectively. Further, Candida albicans was investigated with inhibition zone 7.5 mm. Besides, the insecticidal impact of the nanocomposite against Culex pipiens larvae was performed at 30 mg/l causing 100% larval mortality with LC50 (11.78 mg/l). The micrograph images showed deformations in the larval body as well as egg resulting in zero egg hatchability. Conclusion The fndings approved that synthesized nanorods have a signifcant impact on controlling pathogens that impart diferent diseases to humans and the environment.