Abstract: The cold tolerance provenance′s(CTP) and the common provenance′s(CP) test stands of exotic loblolly pine were planted in the south of Henan Province of China in 1983 and 1984.The differences in tracheid length,tracheid width,tracheid diameter,tracheid wall thickness,tracheid length width ratio,tracheid diameter width ratio,tracheid dull wall thickness diameter ratio were analyzed among provenances of loblolly pine.The differences in most of seven factors among provenances were not significant at 0.05 level.The variant range in one of seven tracheid factors within a given provenance was bigger than that among provenances;There were weak geographical variation patters in tracheid length and tracheid length width ratio of two times provenances.They were negatively correlated with latitude of provenances;At the same growth stage of two times provenances,annual ring width was weak negatively related to tracheid length,tracheid length width ratio,tracheid wall thickness,and tracheid dull wall thickness diameter ratio.And annual ring width was positively related to tracheid diameter,tracheid width,tracheid diameter width ratio.Wood basic density was negatively correlated with tracheid width and tracheid diameter.It was also positively correlated with tracheid wall thickness and tracheid dull wall thickness width ratio.The annual ring width was significant negatively related to wood basic density.These results showed that the causes of fast growth provenances or fast growth individual tree within a given provenance to a great extent was attributed to the increase in width and diameter of tracheid element besides fast division of cambium initial and increase in cell number of unit length.Their tracheid wall thickness did not increase in proportions as tracheid width and tracheid diameter increased.This should be stressed in tree breeding and wood improvement.