Reducing rural income gap is the key to alleviating relative poverty and realizing common prosperity.Based on the 2009-2020 National Rural Fixed Observation Point Survey data，this paper empirically examines the impact of socialized agricultural machinery services on rural income gap using the regression and decomposition of the re-centered influence function （RIF）.The results show that socialized agricultural machinery services are conducive to raising the incomes of low- and middle-income farmers，and the income-raising effect on low-income farmers is greater，which in turn reduces rural income gap.The alleviating effect of socialized agricultural machinery services on the income gap within rural areas exhibits regional heterogeneity，with a greater effect on the eastern region and a smaller one on the northeastern region.The further decomposition results show that the coefficient effect is the main factor in the socialized agricultural machinery services reducing rural income gap，explaining 124.24% of the income gap.Tthe test of the impact mechanism shows that socialized agricultural machinery services reduce rural income gap by promoting rural labor force transfer.Therefore，we should actively promote the development of socialized machinery services，improve the support policies of socialized agricultural machinery services for low-income groups，and give full play to the positive role of socialized agricultural machinery services in alleviating rural income gap.