The paper analyzes the links between liberalization of trade and investment policy reforms and economic growth in Cameroon within 1980-2004. After identifying trade and investment policy reforms and market access conditions, which appears to gear towards liberalization, it appears that their expected results are still awaited. However, facts from the costs/benefits analysis tend to confirm the literature assertion that their long term benefit effects are superior to their short term adjustment costs. Despite the improvement in market access conditions thanks to trade preferences, the country did not take full advantage of that opportunity as well as those offered by trade and investment policy reforms because of the remaining trade, investment, institutional and economic bottlenecks including poor governance and external and mostly internal supply constraints. The growth elasticity determinant forecast model results show that additional reforms in view to lift those constraints are necessary and indispensable to boost growth in Cameroon.