This paper examines the Mackinnon-Show hypothesis i.e. financial liberalization promotes financial depth in case of Iraq. Iraq launched a comprehensive program of economic and financial liberalization since 2003. Thus, this paper aims to answer the key question that “is financial liberalization stimulated the financial depth in Iraq?”. By applying the ARDL Autoregressive Distributed Lag model on quarterly data during the period 2005- 2010, the paper finds that the liberalization of interest rates as a proxy of financial liberalization stimulated the financial depthonly in the long-run in the case of Iraq.