Abstract: In order to prevent and mitigate indoor radon pollution effectively in existing dwellings, the research progress at home and abroad was reviewed from the aspects of pollution status, polluting sources, effects on human health, related control standards and radon mitigation strategies, etc. It is shown that the levels of indoor radon pollution in dwellings of most cities and areas in China have been rising in recent years, mainly due to the building and decoration materials. There exist much different radon levels among foreign countries with different geologies. The indoor radon pollution in dwellings has strong carcinogenic effect on human body and has double risk with smoking. A series of indoor radon control standards and mitigation strategies have been established in China, North Europe and North America. Finally, researches of indoor radon pollution in dwellings at home and abroad were concluded and suggestions on further researches in indoor radon pollution were put forward.