The relationship of soil organic matter (SOC), with soil total nitrogen (TN) and soil available nitrogen (AN) in content was modeled based on the data acquired from an investigation of physical and chemical properties of urban soil in a green space in the centre of Shenzhen City, China. Models were established from the angle of the overall survey, soil pH levels, soil texture types and land-use patterns and screened through data validation. Results showed that SOC was closely related to TN and AN. Though the traditional model of a general linear relationship was adequate to demonstrate the relationship of SOC with TN and AN, models established based on classification of soil types and landuse types were more accurate.