Abstract: The population system is a dynamical system. The population is a very important factor that affects regional economic development，the trend of a population will affect the development of the society and its economy，the accurate population prediction provides a scientific basis for regional planning and decision-making，so it has great theory meaning and realistic meaning to exactly predict development trend of population and establish rational population layout. The model selection of population prediction and scientific confirmation of prediction parameters are two most important basic steps. In this paper，according to 2000-2011 annual statistical data of the total population of Xining City，Qinghai Province，China，the unary linear regression model，Malthusian model，logistic Model and GM（1，1）Model are gained by the least square method. Theoretical and historical simulation examinations show that four models fit well，so these models are used to simulate and forecast the total population from 2012 to 2020 in Xining City. The conclusions indicate as follows：（1）All of the models（the Malthusian model，linear regression model，logistic model，and GM（1，1） model） passed the check for population prediction，and the match accuracy is high；（2） The relative errors of the prediction results of the models are calculated，and verified forecasting accuracy of the models by using a testing value. The results show that the accuracy of predicting values by the models for population prediction in Xining City is above 98%，the mean errors of the unary linear regression model，Malthusian model，logistic model and GM（1，1）model are -0.771 8%，-1.440 8%，0.120 8% and 0.004%，so GM（1，1）model is better than other models according to mean errors；（3）Because that GM（1，1）model is better than the others，so this model is used in population prediction of Xining City：it will reach 2.258 9 million people in 2012，2.333 9 million people in 2015 and 2.463 7 million people in 2020.

Key words: population scale, trend extrapolation, Malthusian Model, Logistic Model, GM（1, 1）Model, Xining City