Abstract: The aim of present research work was to formulate an intravenous injection of Omeprazole sodium. Omeprazole drug is very slightly soluble in water. Hence in-situ conversion of Omeprazole into Omeprazole sodium was opted. But Omeprazole sodium is not stable in solution form. It is stable only for 1-2 days. Hence lyophilization technology was adopted to increase the stability of Omeprazole sodium injection. The lyophilization was carried out in different batches by varying the total cycle time, freezing and holding time, primary drying and secondary drying time while keeping the quantities of all the active pharmaceutical ingredients constant. Lyophilization was carried out in five different batches with five different lyophilization-cycles of 24.5 hours, 28.5 hours, 30.5 hours, 32.5 hours, and 35 hours respectively. Melt pack was found in Batch 1, Partial melt pack was found in batch 2, cake was sticking to the bottom of vial in batch 3, moisture content was high in batch 4, the optimized good cake was found in batch 5. lyophilization cycle of 35 hours was optimized. The optimized lyophilized product was subjected to evaluation parameters such as cake appearance, reconstitution time, pH, assay, impurities, particulate matter, water content and DSC. After considering all product characteristics batch-5 was considered as an optimized formulation. All the evaluation parameters complies the limits as per the specification of USP. Accelerated stability studies were also conducted for a period of three months and from the results obtained, it was found that the optimized formulation was found to be stable. Finally, it was concluded that the lyophilization is a suitable technique to enhance the stability of Omeprazole sodium for intravenous injection with a single dose of 40mg/vial.