Micronutrients and electrolytes deficiencies are prevalent among HIV-infected populations. The use of Highly Active Antiretroviral Therapy (HAART) on the other hand has been shown to increase the life expectancy of HIV infected individuals. The present study was designed to determine the effects of HAART on some serum micronutrients and electrolytes concentrations in HIV positive patients attending Emuoha General Hospital, Emuoha Local Government Area, River State, Southern Nigeria, six months post-therapy. A cohort of 163 patients comprising 111 HIV Positive subjects (25 males and 86 females) and 52 apparently healthy HIV negative controls (11 males and 41 females) were recruited for this study. HIV infection was detected using rapid tests Kits: Alere DetermineTM HIV-1/2 Ag/Ab Combo Rapid Tests Kits (Abbot Rapid Diagnostics, California, USA), Uni-GoldTM Recombigen® HIV-1/2 (Trinity Biotech Plc, Wicklow, Ireland) and Chembio HIV 1/2 STAT-PAK® Rapid Test Kit (Chembio Diagnostic systems, New York, USA). The serum micronutrients and electrolytes levels of the patients were analyzed at diagnosis and 6 months after initiation of HAART using atomic absorption spectrophotometry and ion selective electrode automation, respectively. The outcome of this study show that the mean±SD HAART serum Vitamin A (8.02±0.70µg/dl), Vitamin C (1.21±0.42mg/dl), Vitamin E (0.41±0.02mg/dl), Zinc (89.20±4.73µg/dl) and Selenium (44.42±5.23µg/dl) serum levels of the HIV positive Patients were lower than the controls (9.70±0.93µg/dl, 1.73±0.16mg/dl, 0.67±0.09mg/ dl, 98.48±3.34µg/dl and 55.17±6.02µg/dl, respectively), but significantly higher (P<0.05) than the mean±SD Pre-HAART values (6.32±1.11µg/dl, 0.75±0.09mg/dl, 0.35±0.04mg/dl, 76.20±9.16µg/dl and 23.30±5.91µg/dl, respectively). On the other hand, the mean ± SD serum copper levels of the HAART HIV-positive subjects (31.66±2.33µg/dl) were higher than the controls (26.43±3.34µg/dl), but significantly lower (P<0.05) than that of the pre-HAART (35.12±2.82µg/dl). Furthermore, the results also show that the mean±SD HAART serum Potassium (3.92±0.43mmol/L) and Sodium (134.50±3.27mmol/L) serum levels of the HIV positive Patients were lower than the controls (4.07±0.57mmol/L and 137.46±3.35mmol/L, respectively), but significantly higher (P<0.05) than the mean±SD Pre-HAART values (3.29±0.33mmol/L and 132.61±2.46 mmol/L, respectively). Meanwhile, there was no significant difference (P>0.05) between the mean±SD Pre-HAART (98.92±5.65mmol/L) and HAART (99.59±6.53mmol/L) serum chloride levels of HIV-positive Patients and the Controls (100.42±6.28mmol/L). Also, there were no significant differences between the males and females in all the parameters measured, except for serum vitamin C and zinc levels. On one hand, while the HIV positive males' mean±SD HAART vitamin C serum level (1.46±0.36mg/dl) was significantly higher (P<0.05) than that of their female counterparts (1.14±0.41mg/dl), on the other hand, their mean±SD HAART serum zinc level (89.42±2.45µg/dl) was significantly lower than that of the female...