Abstract: Chinese fir etiolation is a physiological disease which causes heavy mortality of the young hosts,and therefore must be Considered as a problem of major importance#Since the needle etiolation is reflected from rootsystem rot or distorsion,the objective of the work reported here is to show the correlation between the etiolation and the distribution characters of rootsystem of the diseased trees and some of its physiological activation.Four characters of rootsystem abnormality of the diseased trees have been observed,i#e.smaller root length,decreased root number,shallow distribution,in soil and high degree of root rotting.In the test,the diseased trees were found to have lower rates of photosythesis and respiration*And their roots contain much less catalase than that of the sound trees.