The invention discloses a combustion chamber structure and a gas water heater usingthe combustion chamber structure. The combustion chamber structure is applied to the gas water heater; the gas waterheater comprises a fan; the combustion chamber structure comprises a shell, a combustor and an exhaust bracket, wherein a combustion chamber and an opening and an intake hole communicating with the combustion chamber are arranged in the shell; the combustor is accommodated in the combustion chamber, and is provided with a combustion fire port; the exhaust bracket is connected between the combustorand the inner wall of the combustion chamber, and divides the combustion chamber into a combustion cavity communicating with the opening and a guide cavity communicating with the intake hole; the combustion fire port is positioned in the combustion cavity; the exhaust bracket is provided with multiple guide holes at intervals; the guide holes communicate with the combustion cavity and the guide cavity; the guide holes are arranged near the combustion fire port; the fan is arranged near the opening; and the fan pumps air, so that the air is exhausted from the opening after entering the combustion chamber from the intake hole. The combustion chamber structure is lower in tightness requirement, and reduces the vibration and squealing risk.