Optimizing energy structure to reduce carbon intensity is one of the effective ways to achieve low carbon economic development model of environment-friendly and resource-saving.In this paper,firstly,we use the methods such as scenario prediction,GM(1,1) prediction,combined multivariate regression model and Markov chain model to predict the changing tendency of the total consumption of primary energy from 2013 to 2020 as well as its relative variables and energy consumption structure of Shandong province.Secondly,we redefine the definition of "contribution potential" of optimizing energy structure to carbon intensity goal.On this basis,we assessed the potential contribution of the energy structure optimization to carbon intensity in 9 kinds of scenarios in 2020.The results show that: under the same economic growth,the greater the magnitude of energy restructuring is,the carbon intensity "decline" is more,and the "contribution potential" of energy structure optimization to carbon intensity goal is higher.Under the same energy structure adjustment,the lower economic growth is,the carbon intensity "declines" is little,but the contribution potential of energy structure optimization to carbon intensity goal is higher.Even in the scenario of slow economic growth and substantial adjustment of energy structure,the greatest potential contribution of energy structural optimization to carbon intensity target is only 10.9533%.Consequently,optimizing energy structure can contribute to achieving low carbon Shandong to some extent.Nevertheless,Shandong Province cannot achieve carbon intensity target only by energy structure optimization,and the faster economic growth is,the more measures such as industrial restructuring and carbon emissions technology upgrading should be taken.