[en] In order to improve the sensitivity of radon measurement method, Fast and Multi-functional Radon Monitor with Electret, Sensitive Miner Radon Monitor, fast and Multifunctional Radon Monitor with High Voltage and PCMR-1 Passive and Continuous Radon Monitor were developed. Except Sensitive Miner Radon Monitor suits for radon concentration measurement only, the others can be used to measure both radon concentration and radon flux rate. Their measurement principles. specifications, quality assurance system, advantages and disadvantages are introduced. The simultaneous measurement results indicate that the errors among them are less than 5% and 10%, respectively, for the average radon concentration measurement and for the average radon flux rate measurement