Background: Though the earlier studies reported that there will be loss of magnesium and calcium ions in the patients with acute gastro enteritis, the exact measure was not provided. Objective: The present study was undertaken to measure the levels of the calcium and magnesium in the patients of acute gastroenteritis. This information helps to plan adequate treatment in these patients. Materials and methods: A total of 50 patients with acute gastroenteritis aged more than 18 years including both male and females were part of the study after obtaining the written, voluntary informed consent. Unwilling participants were excluded from the study. Patients with any severe complications were also excluded from the study Results; Out of fifty participants, 20 participants were males and 30 participants were females. The range for calcium was found from 6.7 to 10.7 mmol/l. Majority of the patients have the calcium levels in the range of 7.7-8.7 mmol/l. The range for magnesium is 0.1-3.1 mg/dl. Majority of the patients have level of magnesium in the range of 2.1-3.1 mg/dl. Conclusion: Significant decline in the serum calcium and magnesium levels was observed in the patients with gastro enteritis. The study results support the results of earlier studies. The study recommends the need of future studies with involving multiple centers and multiple samples to plan adequate treatment strategies for management of diarrhea cases and to prevent death of these patients.