Abstract: this paper reports the simulation experiments irrigated by wastewater onforest land. The results of the experiments in two years showed that this simulative irrigation system is available for treatment of wastewater from the paper mill. The average removal rate of COD_Mn, SS and the colour of the wastewater is 77.8%, 75.9% and 82.6% in the purple soil, and 96.0%, 86.5% and 97.0% in the red soil. Irrigation with wastewater can speed up the growth of Eucalyptus globulus especially in the red soil. The soil fertility on the irrigated plots has generally decreased than the control but both purple and red soils have increased content of salinity and alkali. The highest content is found in the red soil of Plot No.10, the content of salinity is 0.115%, and the alkalization percentage is 13.8%. In the dry seasons, alkali and salinity can be kept while in the rainy seasons part of them can be removedby soil. Whether the land irrigated by the wastewater from the paper mill will be turned into saline-alkali soil must be further investigated.