Abstract : Water is a precious and essential natural resource with many uses. Its quality must meet certain biological standards. Therefore, it is necessary to know the quality of water store, and conservation method to establish a system that can ensure its quality. The aim of this work is to control the microbiological quality of untreated water stored in in goat leather container (Guerba), and to estimation the maximum storage time. Water samples were analyzed at time intervals including 3 days, 7 days, one week, and two weeks; to assess their bacteriological analysis, which was: detection and enumeration of fecal streptococci, the search for total coliforms, and fecal coliforms Escherichia coli. Sulphite-reducing Clostridiums, The well water samples analysis showed, that it had a poor bacteriological charge, due to the presence of contamination indicators, regarding the water retained in goat leather container, we recorded a slight variation in bacteria charge (total germ 2170 UFC/ml, total coliforms 4,33 CT/100 ml 10³, fecal coliforms 1,6 CF/100 ml 10³ faecal streptococci 2,6 SF/100, sulphite reducing clostridia 1,3 spores/20ml ;this increase in charge, essentially due to the effect of vegetable tar. According to this result it is recommended to use the water stored in leather container in within a maximum period of three days, as the microbiological activity intensifies beyond this time, leading to an increase in pollution parameter values.