Abstract: Bacteriological contamination of well water in Makurdi town, of Benue State, Nigeria was investigated. A total of 15 water samples were collected from hand dug wells and analyzed for total bacteria count as it affect the quality of drinking water for both wet and dry season. The analysis was done according to standard methods of water examination and as reported in WHO guide limit for drinking water. The investigation revealed that the wells examined were highly contaminated with bacteria. Wells 6 and 7 showed highest total bacteria counts of 7.0x105/100 mL and 8. 2x105/100 mL in the wet season, while wells 7 and 2 showed highest total bacteria counts of 8.0x105/100 mL and 5.5x105/100 mL in the dry season. The contamination of all wells could be due to improper construction of wells, refuse dumping sites and various human activities around the wells. Water generally from these wells is not safe for drinking except some form of treatment is carried out.