We studied for the first time the Ecology and biodiversity of underground water in the region of Nord Constantinois (North Eastern Algeria). The results obtained from the investigations of 16 wells and 04 sources from Mars 2015 to Mars 2017 at five administrative regions; Constantine, Mila, Guelma, Skikda and Oum El Bouaghi in eastern of Algeria showed that this aquatic fauna is composed of 25 taxa (families) and 4649 individuals and is dominated by 40% insects and 16% Gastropoda. Only a few stygobitic species were harvested in the study region as the ‘Pseudoniphargussp’, ‘Echinogammarussp’, ‘Thermocyclopssp’ and ‘Eucyprisvirens’. The maximum of diversity is present in wells when the water is of good quality, but it decreases in case of pollution. Stygobitic species are generally more sensitive to pollution than other aquatic sow species, they contain the indicator species of the water quality. The knowledge and this comparative review of the diversity of the fauna of wells located in the same region can be used in a first approach as a base for purposes of monitoring and environmental management.