Abstract:2009 January to 2009 December using years of the negative ion of continuous automatic monitoring data, to Dongguan City Board Mountain Observatory anion concentration diurnal variation, annual variation feature analysis, at the same time the negative ion concentration and relative humidity correlation analysis. The results show that: the concentration of negative ions ( migration rate of 1 ) in the 3 levels above the frequency was 16%; in summer, autumn show higher concentration concentration to achieve the lowest seasonal changes; in the middle of the day were Shuangfeng type variation, maximum value appeared in 3: 00, 00-7: 21 : 00-2: 00., and the minimum appeared in 12: 00 to 17: 00; and weather phenomena, thunder shower ' clear ' Yin ' ' ' mist haze haze rain; and the temperature, humidity, sunshine was negatively related, in which the temperature at 7.2 to 32 DEG C negative ion with the rise of temperature drop; when the humidity in 28% ~ 93% negative ion concentration with relative humidity rises..