Abstract: China's economy is shifting from high speed growth to "new normal" development, the throughput capacity of the port also turn to slow down, the port risk problem is becoming more and more obvious. The development of the port is similar to China's economic development, and showing a very obvious nonlinear development features, it is difficult to describe the realistic problem by using the traditional single model. In this paper, the logistic growth model is initially combined with the Markov model, then logistic growth equation generates the state parameters that Markov model needs, and based on this fact, a risk transfer probability matrix is constructed. So the problem about the port investment risk measure can be effectively solved. The sample data from 1985 to 2014 is selected to verify the results, and the results show that the port investment risk will be highlighted after 2016, and will last for a longer period of time. China's port is currently in a critical period of transformation and upgrading, and it is necessary to accelerate the transition from extensive expansion to the connotation of the development, from extensive to detailed management.

Key words: port throughput, risk index, logistic growth equation, Markov model