Abstract: Disclosed is an airtight container for keeping food etc. in airtight state. The airtight container comprises a body 10 with an opened upper surface; a lid 20 for covering the opened upper surface of the body 10; and a locking portion having at least two locking flanges 40 integrally pivotally coupled to the periphery of the lid 20 through a thin hinge 44 formed at a connecting portion connecting thereof with the lid 20, the locking flange 40 having a hooking protrusion 42 formed on a lower surface thereof, and hooking ribs 50 formed on an upper portion of the outer wall of the body 10, each rib 50 engaging with the hooking protrusion of the locking flange 40.