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Plastic film mulching, known as the “white revolution”, has been widely used in cotton cultivation in China, since it makes the cotton planting area expanded from the south toward the north and from the east toward the west. However, it is unclear about if and how the yield increasing effect of plastic film mulching is influenced by different planting patterns, climatic factors, film thicknesses, regions and experimental durations in China. To solve these questions, a total of 29 papers containing 48 groups of data were selected on the subject of cotton yield and plastic film mulching from the published papers before 15th November, 2016 and analyzed by metaanalysis. The main steps included heterogeneity test, comprehensive effect size calculation, publication bias test, sensitivity analysis, cumulative metaanalysis and influence factor analysis. Results showed that there were no publication bias and no extreme value among the collected data, thus the analysis results were highly credible. Plastic film mulching averagely increased cotton yield by 17.2% compared with no mulching. The cumulatively average yield of cotton mulched with plastic film was increased by 1.2%~18.0% since 1986. Under flat planting, in regions where annual mean temperature was lower than 12℃ or annual precipitation was less than 500mm, and using 0.008mm plastic film, the yield increasing rate under plastic film mulching was higher, which was 17.8%, 21.5%, 19.1% and 17.3%, respectively. The yield increasing effect with plastic film mulching was the highest in the northwest region with a mean value of 24.5%, followed by the Yellow River Basin with a mean value of 16.5%, then by the Yangtze River Basin with a mean value of 10.5%. In recent years, plastic film mulching could improve cotton yield to a certain extent, but its yield increasing rate was declined, and necessary measures needed to be taken. This research would provide valuable information for the application of plastic film mulching and further increase the yield of cotton in China.