Abstract: The effects of three arbuscular mycorrhizal fungi (Diversispora spurca,Glomus versiforme and Paraglomus occultum) on chlorophyll content,root system architecture,tissue glucose and sucrose contents of potted white clover (Trifolium repens) were studied. The root mycorrhizal colonization of white clover ranged from 66.80% to 82.51% 85 days after inoculation. The three arbuscular mycorrhizal fungi,especially G. versiforme,significantly increased shoot,root,and total plant dry biomass production. The inoculated treatments also markedly improved traits of root system architecture,including length,projected area,surface area,volume,tips,forkings,and crossings,which are dependent on mycorrhizal fungal species. G. versiforme showed the best effects on root system architecture of the three mycorrhizal fungi. In addition,inoculation with arbuscular mycorrhizal fungi significantly increased leaf chlorophyll content by 36%-58% and sucrose and glucose contents in leaves and roots,except for the sucrose in roots colonized by G. versiforme. Mycorrhizal colonization significantly positively correlated with glucose in leaves (r=0.852,P<0.01),in roots (r=0.884,P<0.01) and sucrose in leaves (r=0.722,P<0.01). The relationships of arbuscular mycorrhizas,sugar,and root system architecture are discussed.