Abstract: In order to understand the types of volatile organic compounds as well as common monthly and daily dynamic changes of urban green trees sweet gums （Liquidambar formosan） released, we used a dynamic headspace adsorption and thermal desorptiongas chromatographymass spectrometry (TCTGC/MS), to investigate VOCs released of sweet gums in Spirit Valley area on Purple Mountain National Forest Park in October, and discussed the relationship between emissions and environmental factors. The results showed that the flowering sweet gums totally released 43 kinds of VOCs. With vinyl compounds based, accounting for 9419% of the compound content, they were mainly limonene, βpinene and αpinene. Liquidambar formosana released mainly vinyl compounds monthly and the average amounted to 8704%, the highest in August. The release amount of vinyl and aldehydes were summer> autumn> spring. Vinyl compounds increased firstly and then decreased. Vinyl compounds diurnal variation and temperature trend were positively correlated.