Abstract: The adaptation of a winter wheat simulation model to deal with the impacts of increasing CO2 concentration and climate change is described in this paper. The model was validated for the present climatic conditions. The mean relative error of simulation is lower than 10% for the weight of total dry matter and the spike weight at the end of growing period. The simulated values of other organ's weight as well as leaf area index are also well fitted with the observed. Finally, by this modified model the possible effects of increasing CO2 concentration and climate change on winter wheat are estimated.The results show that the rising temperature and increasing CO2 concentration both have positive impacts on winter wheat in Gucheng of Hebei Province and they promote each other for positive impacts.