Fiscal decentralization represents the autonomy granted by the central government to local governments in termsof taxation , budget and debt arrangement , and serves as the guarantee of steadly regional economic growth.Based on the pro-vincial panel data from 1999 to 2019,this paper empirically analyzes the impact of fiscal decentralization on the urban-ru-ral income gap.The results show that although fiscal decentralization can significantly reduce the urban-rual income gupand accelerate the improvement of regional technological innovation ability , the regional technological innovation ability willhave a positive impact on the urban-rural income gap , which will ultimately lead to the loss of the total effect of fiscal de-centralization on the urban-rural income gap.It is found that there is regional heterogeneity in the influence of fiscal decen-tralization on urban-rural income gap and the masking effect of regional technological innovation capability.In eastern Chi-na, the influence of fiscal decentralization on urbkan-nural income gap is not significant.In the central and western regions ,fiscal decentralization can significantly reduce the income gap between urban and rural areas.