Many species of Aeromonas are thought to be the cause of diarrhoeal syndromes, bactaeremia and eye infections. Recent studies have shown that the presence of aeromonas in drinkable water is not associated with that of feacal indicators. The authors have tested 62 samples of drinkable water from various wells, as well as 14 samples of two mineral waters collected in Eastern Sicily from 1996 to 1999. Aeromonas were found in 14 (18%) out of 76 samples. Also, biochemical detection of the strains showed the presence of A. Salmoncida and A. hydrophila. According to the survey's data, there is a need to check aeromonas in drinkable water as a constant practice.