Abstract: Based on the fractal theory,the size distribution and spatial distribution of urban system have been studied.The paper made deep study on the urban system of Fujian Province,and proved that the cale and spatial distribution of urban system both take on fractal structure.The conclusions show that:firstly,the scale of urban system is at the primary first stage,the development of urban system is not yet mature.The biggest town is too big but just single one and the middle towns are absent,so the scale structure is loose;secondly,the spatial structure of urban system is regionally and locally discordant,the spatial distribution is linear,and most towns lie on geographic areas which are the river and road corridor;thirdly,although the spatial relating degree and spatial interaction among cities are generally rapid and intense,the balance of regional urban network waits for the enhancement;finally,the paper discussed the reasons of the urban system’s fractal features,then it pointed out how to improve the urban system by means of fractal theory in Fujian Province. During study on the urban system of Fujian Province with fractal theory,the process and results reveal the following questions:the first one is that to eliminate non-agricultural population to measure the size of towns fractal dimension,and we should access to the urban population census and county urban population size;The second one is that in measuring Town Center radius we should excluden the built-up area,and revise the center of gravity through its radius,as to prevent the fractal dimension calculated diverging from the actual value;Last,the fractal dimension of the measurement accuracy directly impact on the geographic data interpretation,and the theory system needs to be developed in the unity and comprehensiveness in the future.