The study of mosquito larvae in Aswan Governorate has revealed the presence of thirteen culicid mosquito species, ten species belonging to culicinae and three to anophelinae. Culex univittatus (Theobald), Culex pipiens molestus (Forskal), Culex antennatus (Becker) and Aedes caspius (Pallas) were the most common culicine species respectively, while Anopheles pharoensis (Theobald) was the most common anopheline species Many aquatic fauna associated with mosquito larvae were collected during the larval survey. This fauna includes fresh water leeches, fresh water snails, tadoples, Gambusia fish, fresh water prawn, copepods, branchiopods, ostracods and aquatic insects belonging to the orders Ephemeroptera, Odonata, Hemiptera, Coleoptera and Diptera. Gambusia fish, tadpoles and the majority of insects are predaceous on mosquito larvae. Mosquito larvae collected in the present study were infected by flagellated protozoa (Vorticella sp < /em>.), funig (Coelomomyces sp < /em>.) and algae (Odogonium sp < /em>). Vorticella sp < /em>. infect all mosquito larvae except larvae of Culiseta subochrea and Anopheles pharoensis. Coelomomyces sp < /em>. infecting larvae of Culex univittatus only, these infected larvae were collected from Al-Aqabah area only. Odogonium sp < /em>. is an autotrophic green algae attaching only with the larvae of Culex pipiens molestus, Culex antenatus, Culex unitvittatus, Culex theileri and Anopheles pharoensis.