A hermetic compressor, comprising: a casing having a hermetic inner space; an orbiting scroll provided in the inner space of the casing, being configured for performing an orbiting motion; a non-orbiting scroll engaged with the orbiting scroll to form compression chambers; a high/low pressure dividing plate dividing the inner space of the casing into a high pressure portion and a low pressure portion; and an overheat preventing unit coupled to a surface of the high/low pressure dividing plate at the high pressure portion, having a communication hole running through the high/low pressure dividing plate to have the high pressure portion and the low pressure portion communicate with each other, wherein the communication hole is selectively opened and closed according to a temperature of the high pressure portion, wherein the overheat preventing unit includes: a body coupled to the thigh/low pressure dividing plate, the body being provided with the communication hole; a valve stopper coupled to the body, forming a valve space therebetween, wherein the valve space communicates with communication hole; and a valve accommodated in the valve space to open and close the communication hole, wherein the valve stopper is formed with a first gas hole communicating with the high-pressure portion such that one side surface of the valve is brought into contact with a refrigerant of the high pressure portion, and characterised in that the body is formed with a second gas hole communicating with the high-pressure portion, and the second gas hole is formed at opposite side of the first gas hole with respect to the valve such that another side surface of the valve is brought into contact with the refrigerant of the high pressure portion. a casing having a hermetic inner space; an orbiting scroll provided in the inner space of the casing, being configured for performing an orbiting motion; a non-orbiting scroll engaged with the orbiting scroll to form compression chambers; a high/low pressure dividing plate dividing the inner space of the casing into a high pressure portion and a low pressure portion; and an overheat preventing unit coupled to a surface of the high/low pressure dividing plate at the high pressure portion, having a communication hole running through the high/low pressure dividing plate to have the high pressure portion and the low pressure portion communicate with each other, wherein the communication hole is selectively opened and closed according to a temperature of the high pressure portion, wherein the overheat preventing unit includes: a body coupled to the thigh/low pressure dividing plate, the body being provided with the communication hole; a valve stopper coupled to the body, forming a valve space therebetween, wherein the valve space communicates with communication hole; and a valve accommodated in the valve space to open and close the communication hole, wherein the valve stopper is formed with a first gas hole communicating with the high-pressure portion such that one side surface of the valve is brought into contact with a refrigerant of the high pressure portion, and characterised in that the body is formed with a second gas hole communicating with the high-pressure portion, and the second gas hole is formed at opposite side of the first gas hole with respect to the valve such that another side surface of the valve is brought into contact with the refrigerant of the high pressure portion. a body coupled to the thigh/low pressure dividing plate, the body being provided with the communication hole; a valve stopper coupled to the body, forming a valve space therebetween, wherein the valve space communicates with communication hole; and a valve accommodated in the valve space to open and close the communication hole, wherein the valve stopper is formed with a first gas hole communicating with the high-pressure portion such that one side surface of the valve is brought into contact with a refrigerant of the high pressure portion, and characterised in that the body is formed with a second gas hole communicating with the high-pressure portion, and the second gas hole is formed at opposite side of the first gas hole with respect to the valve such that another side surface of the valve is brought into contact with the refrigerant of the high pressure portion.