Abstract Some species of aquatic fungi were isolated during a period of August 2008 to July 2009 .from the environment of Shat – Al – Arab ( represented by Qurna , Garma , and Ashar ) and the aquariums in the Marine Sciences Center and College of Agriculture , some of the environmental factors of thewater sample such as the salinity , temperature , and the pH have been measured . Five species have been isolated and diagnosed as belonging to two genera (Saprolegniaparasitica, S. hypogena, S. ferax , Saprolegnia sp., and Achlya sp.).The enzymic activity of all the isolated fungal species has been examined. The test involves all species of enzymes (Protease, Lipase, Amylase, Phenol oxidase, Keratinase ). All the examined species have given positive results concerning discovering all enzyme. Keywords: aquatic fungi. Enzymes, Saprolegnia , Achlya, protease.