Several studies have highlighted the health hazards of cigarette smoking and other forms of tobacco consumption to include addiction, cancers, cardiovascular diseases, respiratory disorders, and electrolyte disturbances. However, none has reported the effect of aqueous leaf extract of tobacco on blood glucose and plasma concentrations of many electrolytes. This study was designed to find answers to these questions. Ten male albino Wister rats were randomly divided into test and control groups of 5 rats each. Each test rat was given 100 mg of aqueous tobacco leaf extract dissolved in 1.5 mls distilled water once daily for 21 days through an orogastric tube. Each control rat received 1.5 mls distilled water once daily for the same duration. After 21 days, blood samples were collected from each rat for the estimation of plasma concentrations of glucose, sodium, potassium, chloride, bicarbonate, magnesium, and calcium. Blood samples were collected and plasma concentrations of glucose, sodium, potassium, chloride, and calcium determined. There were no significant differences in plasma glucose, sodium, chloride, bicarbonate, magnesium, and calcium in the test and control groups of rats. However, there was a significant decrease in plasma potassium in the test group compared to the control group of rats as shown by the mean values of 5.7 ± 0.25 mmol/L and 6.60 ± 0.25 mmol/L respectively and P value of 0.0005. Orogastric administration of aqueous tobacco leaf extract produced statistically significant reduction in plasma potassium, but not in plasma glucose, sodium, chloride, bicarbonate, magnesium, or calcium in male albino Wister rats.