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Forests are important parts of terrestrial ecosystems and play a leading role in regional and global nitrogen (N) cycles.Detailed assessment of N storage and allocation in China’s forests is critical to improve the accuracy of regional or global N estimates and to guide policy-makers in the formulation of scientific and effective N management measures.However,the fore st N storage at national scale remains unclear.Based on 4420 forest field-investigated data,we investigated the N storage allocation in China’s forests,explored the spatial patterns and influence factors.The data included vegetation information on various organs (i.e.,leaf,branch,stem,and root) and soil information at different depths (0-30 cm and 0-100 cm).The total N storage in China’s forest ecosystems was 14.45±8.42 t N hm-2;0.86±0.51 t N hm-2 (5.95％) in vegetation and 13.59±8.40 t N hm-2 (94.05％) in soil (0-100 cm).The storage and allocation of N varied significantly across various regions and forest types.For different ecological regions,N storage varied from 10.34 to 23.11 t N hm-2,and the allocation ratio of N storage between vegetation and soil (0-100 cm) varied from 0.03 to 0.16.For different forest types,the N storage varied from 12.87 to 18.32 t N hm-2,and the allocation ratio of N storage between vegetation and soil (0-100 cm) varied from 0.03 to0.09.The spatial pattems relative to N storage and allocation in forests were different.Climate was the primary factor influencing the spatial variation in forest N storage,while soil texture was the main factor influencing the spatial variation in N allocation.These first estimates of N storage and allocation ratio in China’s forests are keys for improving the fitting accuracy of regional N cycle models and provide a reference for regional management of forest N.