Regardless the crop production, range and livestock management is unlikely to be possible. Considering the range production is essential for efficient and effective range management. This study aims to investigate the relationship between the rate of forage production and the effects of climate variables. For this purpose, forage yield of four range species including Artemisia sieberi, Scariola orientalis, Stipa atriseta, and Stachys inflate regarded as indices species was recorded in Bidalam rangeland, Fars province, Iran in a 10-year period (1998 to 2007) and then, the study continued for another two years (from 2016 to 2017). Forage yield was collected through cutting and weighing method in 60 random 2m2 plots along four 300 m transects during 12 years. Climatic parameters such as rainfall, temperature, relative humidity and sunshine periods were obtained from Abadeh weather station and used for estimation of forage yield in different growth periods of the year. The annual dry matter production of each species and sum of all species were used as dependent variables and climatic parameters were considered as independent ones using multivariate linear regression. The results showed that previous rainfall (rainy of growing season plus last year) had the highest effect on annual forage production of rangelands (R2=0.88). It was concluded that using regression analysis between annual rainfall and forage production in some indices species, the rangeland production of coming years could be estimated with high accuracy. تفاصيل المقالة