This article estimates the major determinants of agricultural growth and productivity in Iran and investigates ‘growth accounting’ approach to identify the sources of agricultural growth. The theoretical framework is based on this assumption that the identified factors jointly cause total factor productivity growth. This study uses annual time series data (1970-2007) and unit root tests and analyze them using Auto Regressive Distributed Lag (ARDL) model by Pesaran et al.[1]. This co-integration technique accommodates potential structural breaks that could undermine the existence of a long-run relationship between agricultural growth and productivity and its main determinants