In this paper, we combine the input-output approach with fuzzy clustering using the input-output tables of 2011 and 2006 in order to identify the sectoral weights of the Iranian economy. The outliers were separately clustered in order to eliminate their undesirable effects on clustering. The results show that key economic sectors in the manufacturing and mining (non-metallic minerals, basic metals, machinery and equipment n.e.c., distribution of gaseous fuels through mains, other mining, coke and refined petroleum products and nuclear fuels), in Iran are outliers, hence, need to be separately clustered. Moreover, the key sectors are "crude petroleum and natural gas" - "wholesale and retail, maintenance and repair of motorcycles and related parts and accessories, public administration, land transport and agriculture" for export promotion and job creation, respectively.