To provide a flame leakage prevention type gas range for simplifying an exhaust structure and preventing hot air from leaking from a pan fitting section even in a state of a pan removed.

An opening 3a for inserting the pan P is provided on a top board 3 on the upper surface of a gas range body. A Bunsen gas burner 4 is provided at a lower portion from the bottom of the pan P fitted to the opening. A combustion chamber 6 is provided to surround the periphery of the pan P fitted to the opening and that of the gas burner 4. An air curtain generator 41 for supplying air in parallel with the top board 3 is provided at the upper portion of the combustion chamber 6. Then, an exhaust passage for allowing the upper portion of the combustion chamber to communicate with an exhaust cylinder 7 is provided. An air curtain is formed at the opening 3a, thus preventing hot air in the combustion chamber from leaking upward from the opening. The combustion gas and hot air flow along the air flow of the air curtain and are discharged to the outside of the heater body via the exhaust cylinder 7.