Mainly according to a growth pole theory and based on researches of features of Chinese inter - provincial migration since the opening up and reform, this paper makes an analysis of population migration's influence on the economic polarized growth in three metropolitan regions, and finds that population centralization there boosts economic polarized growth mainly through its stimulating quick developments of service industry. It is also found that because of an increasingly migration, the economic growth curve shows itself a monotonous rise quadratic. This indicates that the economic growth in the three metropolitan regions has entered a new and accelerating stage. However, the immigration emphasis has obviously transferred from the north to the south. That is to say, the spatial distribution model of immigration flow has changed spatial model on gradually from "throe poles" to "single pole". Therefore, the model should be changed and a new the three metropolitan regions' coexistence and mutual facilitation should be built up.