Background: Malaria is a major health problem in india . it is one of the biggest burdens in terms of morbidity and mortality. Malaria pathogenesis is based mainly on extensive changes in haematological and biochemical parameters. Aim:1)To study the spectrum of disease 2)To study the complication 3)To study prognosis and outcome in Malaria Method: This observational study enrolled Total of 100 cases of P.Vivax Malaria (63 male and 37 female).Detailed examination and routine investigation were carried out.All patients were screened for complication. Result: This observational study reveals male predominance.Large number of patients belonged to age group 20–40 years. Fever was intermittent in most of cases. Thrombocytopenia was remarkably common and was found in 80% with 8% of patients had severe thrombocytopenia.Reversible renal impairment (serum creatinine >3 mg%) was found in 15 patients but none of them required hemodialysis or exchange transfusion. Conclusion: Although a benign disease in majority ,vivax malaria dose have a propensity to cause complications.