The incidence of diabetes mellitus has increased globally making it a major public health concern. Diabetes mellitus is the most common metabolic disorder that causes an imbalance in the electrolytes which regulate essential metabolic mechanisms of the body. This study aimed to estimate the electrolyte levels in Libyan patients with type II diabetes mellitus and to investigate their relations to glycemic control and body mass index. A total of 122 Libyan subjects whose ages ranged between 35 years and 60 years for both sexes were included in this study, 77 patients were type II diabetic patients (37 males and 40 females) and 45 subjects were healthy individuals (23 males and 22 females) live in Tripoli area, Libya. The levels of blood glucose, HbA1c, sodium, potassium, chloride, magnesium and calcium were estimated in this study along with the measurement of body mass index, and systolic and diastolic blood pressure. All the findings were statistically analyzed by one-way ANOVA test. Significant increases in glucose, HbA1c, potassium, chloride, calcium, blood pressure and BMI among diabetic patients were observed as compared to the healthy individuals. On the other hand, significant decreases in sodium and magnesium levels among the diabetic patients were observed as compared to the control group. In addition, significant alterations in all the biochemical parameters in uncontrolled diabetic patients as compared to the controlled diabetic patients, and in unhealthy weight diabetic patients as compared to the healthy weight patients. It is concluded that diabetes mellitus results in an imbalance of electrolytes. Poor glycemic control and obesity have adverse effects on electrolyte balance among diabetic Libyan patients. Good glycemic control, maintaining a healthy weight and regular evaluation of electrolytes among diabetics can reduce the fatalities associated with electrolyte rearrangements.