Background: Member countries of the Organization for Economic Co-operation and Development (OECD) have experienced a downward trend in capital and macro investment returns. Countries rely on investments in healthcare and health-related sectors to ensure continuous input and an efficient labor market. Public healthcare coverage is a social welfare policy implemented by governments, which contributes to improving human capital quality and ensuring stable economic growth. Methods: This study employs a method that combines theoretical modeling and empirical testing examining 33 OECD countries from 2001 to 2017. We first construct a nonlinear dynamic panel threshold model to examine the impact of public health spending on economic growth. We then employ the model to empirically analyze the threshold effect of public health expenditure on economic growth, validating the effectiveness of our theoretical model. Results: When the level of household consumption is below the 9.63 threshold, the effect of public health expenditure on economic growth is significantly negative (p 0.1), and it becomes significantly positive when it exceeds 10.57 (p