The relationship between finance and growth is the topic of debate during the last decade of economists. This study was conducted to examine the causal relationship between financial development and economic growth through trade openness for the period of 1995 - 2015 in the ASEAN-6 countries (Indonesia, Philippines, Malaysia, Singapore, Thailand, and Vietnam). The results show that financial development and economic growth are, through trade openness, found to have bidirectional relationships. This implies that there would be shortcomings while ignoring the presence of the third variable – trade openness which has a positive impact on the relationship between finance and growth.