Abstract: Based on the Landsat TM/OLI images in 1987, 1990, 1994, 1998, 2002, 2007, 2011 and 2015, and GIS spatial analysis method, the urban spatial expansion characteristics of Liaocheng city in the North China plain were analyzed since 1987 years based on the indexes of the intensity of urban spatial expansion, compact ratio, fractal dimension and gravity coordinates. The driving forces of temporal and spatial expansion characteristics of Liaocheng city were also systematically analyzed by some statistical data. The data show that: Liaocheng’s built-up area has expanded each year from 1987 to 2015, and the area increased from 20.81 km² in 1987 to 123.87 km² in 2015; annual expansion area is about 3.68 km², and the extension strength is 17.96%; the compactness of the city decreases with fluctuations; the fractal dimension increases gradually from 1987 to 2002,then fractal dimension decreases from 2002 to 2011 and rises finally; the analysis of city expansion direction showed an easterly shift and city morphology is tending to the condition of “expand-infill-re-expand”. Studies on the driving forces show that natural environmental factors are the foundation of the urban expansion, economic development and urban expansion can promote each other, and that traffic construction and government policy are the main driving forces for the urban expansion. This study will help understand the expansion characteristics of the similar cities in the North China plain.

Key words: urban spatial expansion, urban morphology, Landsat, Liaocheng city, North China plain