OBJECTIVES: To study the frequency of electrolyte and blood glucose imbalance at admission in children admitted to a Pediatric Intensive Care Unit (PICU). METHOD: Prospective study comprising of critically ill children admitted in Pediatric ICU of a tertiary care centre of North Karnataka from November 2015 to April 2017. RESULTS: One hundred and fifty three patients aged 1mo to 15y, were admitted to the PICU during the study period. The mean age was 4.8 y. The male: female ratio was 1.2:1.128 patients (83.7%) had electrolyte abnormality. Hypochloremia was the most common electrolyte abnormality, followed by hyponatremia, hyperglycemia. Most common system involved was CNS, followed by Respiratory illness. Out of the 153 patients, 96.1% were discharged, 3.3% were discharged against medical advice, 0.7% died. CONCLUSION: Serum electrolyte and blood glucose abnormalities are very common in critically ill patients and can lead to fatal consequences. In view of these facts, a routine estimation of serum electrolytes and blood glucose should be considered in all patients getting admitted to PICU.