The Global-Malmquist index based on SBM super efficiency model was used to measure the land use efficiency of 26 cities in the Yangtze River Delta, and the impact of land finance on land use efficiency was analyzed by the Spatial Dubin model. It is found that, firstly, urban land use efficiency in the Yangtze River Delta presents a stable development trend, with a relatively high overall efficiency level and spatial agglomeration characteristics. Secondly, land finance has a statistically significant negative impact on land use efficiency. Thirdly, the mechanism test shows that the negative impact of land finance on urban land use efficiency is mainly realized by inhibiting technological progress.