A preliminary study on the distribution and tensile strength of roots of Cynodon dactylon L.in soil was conducted.The results showed that the density and the weight of root decreased with the increasing soil depth(0.40cm),and the trend could be expressed by exponential function.The tension resistance of the root increased with the enlargement of diameter,and could be modelled by quadratic function.The average tensile strength of the root was 39.349 MPa,and was 17% of that of grade I steel,more over,it decreased with the increase of the diameter,and submitted to the law of exponent ial function.Hence,Cynodon dactylon L.has a significant function in slop protection based on the root distribution characteristics and tensile strength features.