Abstract: Based on 688 permanent sample plots，the whole stand growth model of BP ANN was developed for natural dahurian larch(Larix gemelinii Rupr.) forests in area of the Daxing’an Mountains, using log-sigmoid function (logsig) and linearity function (purelin) of MATLAB as the neural functions. According to the concept of whole stand growth model，the Age(A)，Site Class Index (SCI) and Stand Density Index (SDI) were considered as input variables and the Stand Volume(M) was as the output variable in the model. A comparative study between BP ANN model and the common method was also conducted. The result of the model performance analysis was showed that the BP ANN model in this paper had high fitting accuracy (99.6%) and precision (98.9%), it is better than the common methods in fitting and adaptability and it was suitable to predicting stand growth.

Key words: BP ANN, Dahurian Larch(Larix gemelinii Rupr.), natural forest, whole stand growth model