The paper evaluated the water conservation function of forest in the south mountainous area of Jinan City

using the reflection engineering method

on the basic of the study of the substance quantity of water conservation of the forest. The result was that the whole value of water conservation of the litter-fall floor was 0.578 3 million yuan

the whole value of water conservation of the soil floor was 59.387 4 million yuan

the value of increasing valid water in th eperiod of low water was 44.630 2 million yuan

the value of purifying water was 89.501 0 million yuan and all the value of water conservation was 194.096 9 million yuan. The study provided scientific basis for the evaluation of water conservation function of forest in the area and it was useful for the construction of environment in Jinan City.