Abstract:Th elates of ~(14)C-atrazine and urea;~(14)C-atrazine,n-sodium dodecyl- benzol-~(14)C-sulfonate and urea;sodium dodecylbenzol-~(14)C-sulfonate and urea;as well as sodium dodecylbenzol-~(14)C-sulfonate,n-atrazine and urea under indoor simulsted natrral conditions were reported in thi paper.The distinction of behaviour,including distribution,coversion,mineralization and volatility of ~(14)C-labelled chemicals between the three chemical mixtu- res and atrazine with urea or sodium dodecylbenzol sulfonate with urea in soil-maize system was also compared.The distinction of the influence of the chemical mixture from atrazine and urea or sodium dodecylbenzolsulfonate and urea on nitrogen balance in this system was studied.It will be helpful to evaluate their influence on crop quality and agricultural environment quality.