An object of the present invention is to provide a method for producing a hermetically sealed container, which method comprises conducting hermetic sealing of a container for beverage or food using a laser welding method, whereby the process speed of the sealing process can be made fast, strict control of the scanning position of laser spots is unnecessary, partial oversupply of energy does not occur easily, and there is no reduction in the welding area or welding strength per area due to the gathering of water drops.The method for producing a hermetically sealed container for beverage or food according to the present invention is characterized in being a method for producing a hermetically sealed container for beverage or food, the method comprising a container body and a lid mounted on the mouth portion of the container body according to a laser welding method to an airtight state, wherein the method comprises a process of welding the entire intended welding site of the container body and the lid simultaneously or almost simultaneously.