This paper analyzes the threshold effect of public debt on economic growth in ASEAN countries. The dynamic panel threshold model was employed in the research to test hypotheses of the data collected from some ASEAN countries in 2002 - 2020. The results show that the average public debt-to-GDP threshold of the ASEAN countries is 95,7%. If public debt is lower than this threshold, its contribution to economic growth is positive. In contrast, public debt-to-GDP exceeding the threshold ratio harms growth. In addition, the paper also shows that the public debt threshold of ASEAN countries is in the range of 52,5% - 97,7%. Therefore, economic policymakers should propose a public debt threshold consistent with expanding fiscal policy and increasing public debt to promote growth.