Disclosed is an airtight container in which a lid is easily opened by the principle of the lever thus preventing broth from splashing out when the lid is opened. The airtight container includes a container body having a latching bump and a bent flange, a rotating knob connected to the flange and having an opening-closing plate and a step portion, and a lid having a latching protrusion, a downwardly bent flange and a lid extension portion, wherein, when the rotating knob is just rotated upward in a state where the lid is coupled to the container body, the opening-closing plate lifts the lid extension portion by “the principle of the lever” while the step portion prevents the lid extension portion from spreading outwards, thereby allowing the latching protrusion to be released from the latching bump and the lid to be opened from the container body.