Giza governorate has unique characteristics which induces mosquito proliferation and thus magnified the risk of diseases transmission. In the present study, entomological field surveys integrated with lab analysis were utilized to characterize water quality associated with mosquito breeding habitats in the Nile Valley zone of Giza governorate. Field survey was conducted for a total number of 20 accessible breeding sites during the period of 6th –9th December 2019. From each visited site, mosquito larvae and water were sampled to identify larval species and analyze physico-chemical characteristics of water. Fourteen different water quality parameters were measured including; pH, Total Dissolved Solids (TDS), Oxidation-Reduction Potential (ORP), Conductivity (EC), Turbidity, Chlorophyll, HDO, Crude Oil (CO), Salinity, OM, Phosphate ion (PO43-), Nitrate ion (NO3-), Cadmium (Cd), Lead (Pb). Spearman correlation coefficient was used for data analysis. A total of 8,435 mosquito larvae belonging to 4 species representing one genus were collected from fixed larval breeding places. Culex pipiens was the dominant species except in two sites where Cx. pusillus and Cx. theileri were predominant. There was a significant positive correlation between the density of Cx. pipiens and Cx. perexigues and salinity, OM, nitrate, phosphate, and heavy metal, except that the correlation between Cx theileri and phosphate is negligible. It could be concluded that the correlations observed between physicochemical factors and larval species confirm the effect of these parameters on the breeding activities of mosquitoes and may be suggestive of the presence of certain mosquito fauna in a given region.