Taking Pinus tabulaeformis,Platycladus orientalis,Robinia pseudoacacia and Ouercus liaotungensis forests in the same period in the Beijing low mountain area as a case,this paper studied evaluation on health conditions of different tree species and different standing forests for soil and water conservation.Through the construction of the evaluation system,the establishment of a comprehensive evaluation model,calculation of the stand comprehensive evaluation index,different forest stands were evaluated.Then the soil and water conservation forest was divided into four classes： the first class forests for soil and water conservation with comprehensive evaluation value of S≥8;the second class with 5≤S〈8;the third class with 2≤S〈5;the fourth class with S〈2.Then growth conditions and site characteristics of the different types of forest for soil and water conservation was discussed,and a reasonable improvement measures was proposed.