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Increasing phosphorus (P) deposition induced by anthropogenic activities has increased the availability of P, and thus could affect ecosystem carbon cycling. Although soil respiration (R-s) plays a crucial role in driving the global carbon cycle and regulating climate warming, a general pattern reflecting the R-s response to P addition in terrestrial ecosystems remains unclear. Here, we conducted a meta-analysis from 102 publications to explore the generalities and mechanisms of responses of R-s and its components to P addition across various ecosystems at the global scale. Our results showed that P addition did not significantly change R-s and heterotrophic respiration (R-h) across all ecosystems, but this P addition effect varied among ecosystem types (p < 0.05). Specifically, P addition significantly increased R-s by 17.4% in tropical forest and by 31.7% in cropland, depressed R-s by 13.7% in wetland (p < 0.05), and had minor effect in other ecosystems (grassland, boreal forest, and temperate forest). In contrast, P addition did not have significant effect on R-h within any specific ecosystem type. Among multiple environmental and experimental variables, mean annual temperature might be the fundamental driver indirectly controlling the response of R-s to P addition at the large scale. In addition, P addition increased soil P availability, and changed ecosystem carbon pools and fluxes. The responses of R-s and R-h were significantly positively correlated with those of soil organic carbon, microbial biomass carbon and belowground biomass, respectively, suggesting that changes of these carbon pools may drive the responses of R-s and R-h to P addition. Collectively, our findings imply that R-s in tropical forests would strongly respond to P enrichment where current soil P availability is low and future P deposition rate is high, provide a framework for understanding R-s dynamics under global P deposition, and highlight the need for further field studies partitioning the two components of R-s.