Rice production is sensitive to the climatic factors such as rainfall, maximum temperature, minimum temperature, sunshine and humidity etc. So, any change of the climatic variables will affect the production of rice. This study investigated the effect of climate parameters on Aman rice production in Rangpur district, Bangladesh for the last 3 decade (1987-2015). The research on the effect of climatic variables on rice production is not rare in Bangladesh but the findings are not converged to any direction despite their similarities on data and study areas. The conducted studies used different analytical methods and obtained different results. Aman rice growing period partitioned into three stages: vegetative, reproductive and ripening. Maximum, minimum and average of the variables calculated by MS Excel. A dummy variable created and autocorrelation, multicollinearity, heteroscedasticity and linearity assumption checked by using Statistical Package for Social Science. Stepwise linear regression feature of SPSS had been used to fit the crop climatic regression model. The model showed that increased average humidity in ripening stage and maximum sunshine in vegetative stage decreased the quantity of yield while increased average rate of continuous day?s rainfall in vegetative stage has positive effect in the yield. So, effect of average rate of continuous day?s rainfall is becoming the dominant variable continuously for Aman rice production in the last three decade of Rangpur district.