Proceedings of 3rd Global Accounting, Finance and Economics Conference 5 - 7 May, 2013, Rydges Melbourne, Australia, ISBN: 978-1-922069-23-8 Inventory Investment and its Relation to the Sectoral GDP in Saudi Arabia Hamed Alhoshan and Abdullah Alshebel The relationship between inventory investment and GDP has been investigated and documented for various countries in the world by many researchers. Most of the studies examined the extent of the contribution of the inventory investment to the volatility of the GDP growth. The method of analysis in this regard ran fro a simple co-variance and correlation analysis to the more sophisticated time series methods. In this paper, however, we attempt a different them of analysis. That is we intend to investigate the causal relationship and the cointegration if possible between the inventory investment and various types of Saudi Arabia GDP. Saudi Arabia is an oil based economy, therefore its total GDP is in fact disaggregated into three types of GDP; oil GDP, private GDP, and the government GDP. The inventory investment, or the change in inventory to be precise, is reported in an aggregated manner. Therefore, the question is which of these types of the GDP is more related to the inventory investment and what the direction of the relationship is. Using annual data for the period 1968 to 2011, we tested the causal relationship by the mean of Granger causality approach. Further, we tested both the short run and the long run causality. Our primarily results indicates that for the inventory and the government GDP, both types of causality run from the former to the latter. While in the other two cases, our findings suggest that there is long run causality runs from the inventory to the privet GDP, and short run causality runs from the inventory to the oil GDP. _________________________________________________________ Hamed Alhoshan and Abdullah Alshebel, Department of Economics, King Saud University, Saudi Arabia.