As an important ecosystem in a city, urban forest plays a vital role in the stability of urban environment and the whole ecosystem. By using the CiteSpace V software, the reach literature of “urban forest” in the core collection of Web of Science analyzed visually, and the clear knowledge map was obtained, which has important reference significance for the study of urban forest in China. The result shows that: 1）The 10-year period from 2004 to 2014 was the prosperous period of international urban forest research, which has produced the largest number and the most influential research literature. 2) In the development of international “urban forest” research，the study of Fragmentation was in the core position , combining the other three clusters of Wildland-urban interface，Water quality and Outdoor recreation，formed the foundation position in the overall research process．3) Nowadays currently，the research hotspots of international urban forest study mainly focus on three aspects: the health status of urban forest ontology，the function of urban forest ecological service，and the stability of urban forest to the whole ecological environment．4)Generally speaking, compared with domestic research, the international research on urban forest has more advantages in terms of depth and dimension，which is worth of reference.