Objective The survival analysis method and mixed effect model are combined to construct tree mortality model and improve the simulation precision of the model.

Method Taking 20 plots of Larix olgensis-Abies nephrolepis-Picea jazoensis mixed stand in Wangqing Forestry Bureau of Jilin Province as examples, the tree mortality and survival model were constructed based on Cox proportional hazard function of survival analysis method, and the stand factor and site factor was added into the model as covariates. The plot’s random effect was considered and compared with the simulation effect of the traditional model.

Result It showed that the Cox proportional hazard function model had fitting goodness in describing tree mortality. The initial DBH of tree was negatively correlated with the hazard function of the tree, and positively correlated with survival rate. The BAL was positively correlated with the hazard function of the tree, and negatively correlated with survival rate. The initial stand density per hectare was positively correlated with the hazard function of the tree, and negatively correlated with survival rate. Compared with the fixed effect model, the accuracy of Cox proportional hazard function model was greatly improved after considering plot’s random effect. Because the BAL and initial stand density per hectare showed no significant effect after considering the plot’srandom effect, only the initial DBH was considered, and the difference also reached a significant level.

Conclusion In forest management, the Cox proportional hazard function model provides a good basis for determining the reasonable management density for forest operators.