摘要:The quality of groundwater is three fold: physical, chemical and biological. For water to be fit for human consumption, it must have satisfied all three quality aspects. Therefore, the groundwater biological quality of Abuja FCT can never be over emphasized since the wellbeing of the citizens of the capital territory, seat of the government of Nigeria, is of strategic importance. There are myths and realities about the biological quality of groundwater in fractured rock aquifers which must be clarified. Groundwater plays a very important role in the development of Abuja, Nigeria’s Capital as many private, government, and households establishments depend solely on hand-dug wells and boreholes for their daily water needs. This study evaluates the biological quality using total bacterial density (TBD), total coliform (TC), coliform bacteria (CB), faecal coliform (FC), total bacteria count (TBC), and salmonella species (SS) as biological pollution indicators. From physicochemical parameters: pH ranged from, 4.8 - 7.9; EC, 13.4 - 1634 μS/cm; Temperature, 26?C - 36.1?C and TDS, 17.42 - 1094.78 mg/L. Groundwater of Abuja FCT is not suitable for drinking as the species had the following concentration and percentages above the permissible limits for drinking water: TC (0 - 1280) 51.06%, FC (0 - 170) 19.15%, TBD (0 - 86.6) 98.94%, TBC (0 - 5120) 95.74%, CB (0 - 438) 74.47% and SS (0 - 223) 69.15%. Groundwater from Abuja FCT Granite-Gneiss fractured rock aquiferous formation is unfit for human consumption and an added danger to humans since it is usually assumed to be safe. Groundwater from Granite-Gneiss fractured rock aquifers could be the source of endemic outbreaks of waterborne diseases such as E. coli, Cholera, Gastroenteritis, Typhoid and Diarrhea; as such all groundwater from the aquiferous formations in Abuja FCT should be treated before consumption and use. Source protection strategies as well as monitoring are recommended although it may not serve the purpose for which it is intended since the potential for pollution is point and non-point sourced.