Atmospheric nitrogen deposition was a highlight of global change research. There were limited studies so far on the impacts of nitrogen deposition on the increasing urban green spaces. To clarify such effects on the typical urban grasses (Cynodon dactylon) and the soil chemical properties, one control experiment was conducted for one year term, in which NH_4NO_3 was added as the external nitrogen sources with four treatments of nitrogen addition (0 g·m~(-2)·a~(-1) (N0), 5 g·m~(-2)·a~(-1) (N1), 10 g·m~(-2)·a~(-1) (N2) and 15 g·m~(-2)·a~(-1) (N3)). Results showed that: (1) The above and underground biomass and the density of the green grass reached maximum with the N1 treatment, while the plant height was maximum with the N2 treatment. The ratio of root-shoot was decreased with the increasing nitrogen addition from N0 to N3. Appropriate amount of nitrogen deposition is beneficial to the growth and biomass accumulation of plant. However, seasonal variation of precipitation may affect the nitrogen absorption and utilization of plant. (2) The soil pH was decreased with the increasing nitrogen deposition. Low nitrogen deposition could neutralize the alkaline soil. (3) With the increase of nitrogen deposition, the available nitrogen content was increased. The increasing of nitrate nitrogen and ammonium nitrogen would increase the productivity of urban green spaces. These results showed that nitrogen deposition will have a sustained impact on urban green space (UGS). To some extent nitrogen deposition would increase the productivity of urban green spaces.