This paper describes the design of ^222 Rn/^220Rn sampling monitoring and control system based on single-chip microcomputer of series Intel51. The hardware design involves the choosing and usage of sensors-chips, A/D conversion-chip 、 USB interface-chip 、 keyboard-chip 、 digital display-chip, photoelectric coupling isolation-chips and drive circuit-chips of the direct current pump. Software design is composed by software of Personal Computer (PC) and software of Single Chip Microcomputer (SCM). The data acquisition and conversion and the...