Global terrestrial ecosystems commonly experience soil nitrogen (N) deficiency. Legume/non-legume intercropping systems, utilizing the biological N fixation potential of legumes, represent a promising strategy to enhance resource use efficiency and agricultural sustainability. This meta-analysis synthesized data from 74 global studies (276 combinations) to evaluate the effects of intercropping on the growth of non-legume plants, soil properties, and N transfer. Results indicated that intercropping significantly increased non-legume productivity (yield by 33.13 % and total biomass by 21.14 %), and elevated soil N availability and arbuscular mycorrhizal fungi (AMF) colonization. Interspecific N transfer in intercropping systems was confirmed as a key mechanism, the proportion of N transferred from legume varied from 0.54 % to 52.8 %, and the proportion of non-legume N derived from transfer was 0.07∼78.33 %. Their magnitudes were context-dependent, showing higher efficiency in field and forage systems than pot experiments. Crucially, management practices significantly regulated N transfer process. High legume planting proportions and AMF inoculation promoted N transfer while N fertilization suppressed it. In conclusion, legume/non-legume intercropping systems effectively promotes the growth of the non-legume crops by enhancing soil N availability and facilitating interspecific N transfer. Our meta-analysis provides scientific support for legume/non-legume intercropping as a sustainable approach to improve crop production.