In this study, urban climate in Nanjing of eastern China is simulated and examined using a 1-km resolution Weather Research and Forecasting (WRF) model coupled with a single layer Urban Canopy Model (UCM). We first evaluate the results from fine-resolution model simulations for 10 summers from 2000 to 2009 and find the WRF model is capable of capturing the high-resolution features of urban climate over Nanjing area. Although WRF underestimates the total precipitation amount, the model performs well in simulating the surface air temperature, RH, and precipitation frequency, diurnal cycle and inter-annual variability.