Abstract: Based on field investigation and data collection, we estimated the distribution pattern and driving factors of naturalized plant species in 48 prefecturelevel cities in four provinces (Heilongjiang, Jilin, Liaoning and Inner Mongolia) of Northeast China. We found 370 species from 239 genera and 70 families of naturalized plant species in this area. Among those species, Asteraceae, Poaceae and Fabaceae had the largest proportion of species. About 70% of the naturalized species were introduced artificially, with Europe as the largest source area. There was substantial spatial variability in species diversity, with a decreasing trend from east to west in prefecturelevel cities. Naturalized 〖HJ*5〗species distributed more in capital cities or coastal cities, such as Shenyang, Harbin, Hohhot and Dalian, while less distributed in plains and grasslands. GDP, land use intensity and mean annual temperature were major driving factors. By Logistic fitting, we found that the number of naturalized species in our study region tended to be stable. However, more exotic plant species may be introduced in the future with the implementation of “Northeast Revitalization” policy, which should be paid more attention.

Key words: developmental threshold temperature, temperature, life table, effective accumulated temperature, population trend index.