In this paper, using a panel causality approach, we examine endogenous connections between financial development, innovation, and economic growth in OECD countries for the period 1961-2018. The empirical results of our study show that financial development and innovation support long-run economic growth and that the short-run dynamics facet the multifarious interconnections between financial development, innovation, and economic growth. The strategic insight drawn from this research is that to ensure sustainable economic growth, policy-makers in the OECD countries must pay attention to establishing an integrated structure that looks into co-improvement policies concerning the activities that enhance financial development, innovation, and economic growth. © 2021 World Scientific Publishing Company.