Abstract: Fine hourly meteorological data are the basic for the studying climate feasibility.Based on the four times a day of observational data and daily maximum and minimum air temperature data at five meteorological stations in He'nan province,the hourly air temperature was calculated using a cubic spline interpolation method,and the differences between observed and simulated air temperature were analyzed based on the observations of Zhengzhou meteorological station from 2006 to 2015.The results show that the cubic spline interpolation method can effectively represent the variation of the actual air temperature.Through considering the daily maximum and minimum air temperature,the "six-point" interpolation model is better than the "four-point" interpolation model.The simulated and observed values of air temperature have a significantly high correlation (R²=0.99,n=730 40).The cubic spline interpolation method can effectively convert the four times observation data into hourly data,especially as temperature values do not have continuous jumps.This method can also be used to simulate hourly variations of other continuously changeable parameters,such as water vapor pressure,relative humidity,wind speed and their simulations are hardly limited by territory.The deviation and variation between the simulated and observed air temperature at the Zhengzhou meteorological station prove that the simulation results can meet the requirements of time accuracy of meteorological elements and climate application service.