A number of 50 Ardeola ibis ibis birds were found harboring six nematodes species; Tetrameres species, Microtteramere species, Synhimantus invaginatus, Synhimantus equispeculatus, Ascaridia species, Paracamallanus species,and five species of trematodes; Euclinostomum heterostomum, Nephrostomum ramosum, Apharyngostrigea ibis, Apatemon gracilis and Centrocestus armatus. The most common infection by nematodes was (46%) in which highest infection rate Synhimantus invaginatus recorded (30 %) while the trematode infection was (24 %) and Apatemon gracilis was the most prevalent (16 %). Experimental infection of buff backed heron by encysted metacercaria (EMC) and exysted metacercaria (ExMC) of Clinostomum complanatum from freshwater fish Tilapia nilotica, resulted in adult worms formed after 6 days. Where the infection by EMC recorded higher worm burden (14-18 worm) and hatching percent (78%) while the infection by ExMC gave lower worm burden (7-10 worm / bird ) and hatching (48 %). In the present study, it is worthy to mention that buff backed heron act as final host model for Clinostomum complanatum and this will be helpful in further biological and immunological studies for this trematode to decrease its economic losses in fish intermediate host.