In order to explore the influence of log waterfall structure on temperature field of river hyporheic zone, a two-dimensional coupling model of surface water and groundwater was established by using the finite element software COMSOL Multiphysics, and the influence effects of log structure height, spacing and quantity on the temperature field was explored. The results show that the addition of log waterfall structure in the river can change the pressure distribution in the hyporheic zone, and increasing the height, spacing and the number of log structures can magnify the maximum pressure of the river bed. As the height of log waterfall structure increases, the temperature of the area below the logs is affected more widely by the surface water temperature. Thermal buffering of the hyporheic zone can be enhanced when the spacing and number of log waterfall structure increase. Variation of log structure parameters can affect the temperature field and thermal buffering in the hyporheic zone, resulting in thermal heterogeneity, which may increase the diversity of benthos and aquatic habitats. Keywords: river hyporheic zone; log structure; surface water-groundwater coupling model; temperature field; thermal heterogeneity 〖FL