The invention discloses a 
gas heater, and belongs to the technical field of heating equipment. The problems that an existing 
gas heater easily generates unsmooth air flow in the use process, and harmful gas is generated and threatens the life safety are solved. According to the technical scheme, the 
gas heater comprises a shell, a 
combustion platform is arranged in the shell, a fire grate, an airinlet 
pipe and an igniter are arranged on the 
combustion platform, an air guide 
pipe communicating with the outdoor position is further included, a cover body is arranged on the 
combustion platform, and a 
smoke discharge channel communicating with a combustion cavity and an air 
inlet channel communicating with a cavity are formed in the air guide 
pipe. According to the gas heater, when 
waste gas generated by combustion in the combustion cavity enters the 
smoke discharge channel, heat is transmitted to the indoor position, the outdoor air enters the cavity through the air 
inlet channel, and finally enters the combustion cavity to supply 
oxygen, when the gas amount is increased, the speed, passing through the air 
inlet channel, of outdoor air is correspondingly increased, 
oxygen can be supplied in time, the problem that the 
airflow is not smooth is avoided, and meanwhile, the 
waste gas is isolated from the indoor position to ensure life safety.