The concept of Smart City is changing the methods by which the cities manage urbanization strategies and govern city. The article on hand uses the dataset of nine cities of Guangdong, Southern province of China, to examine what social powers influent cities towards their smartness, and how they affect. It shows the influential social powers can be classified as four groups, personnel, capital, material and intellectual resources. After factor analysis, unit root test, cointegration test, Granger causality test and regression analysis, we found that, in the growth mechanism of smart city, the most important impetus force is financial resource, knowledge resource the second. Furthermore, in the progress towards smarter, the city will accelerate the accumulation of social resources. The results of this paper indicate the effect and efficiency of the strategy implementing in Guangdong Province.