The study will investigate the relationship between external public debt and economic growth in Bangladesh for the period 1974 to 2010 using some econometric tools. Long run significant relationship has been found to have negative effect of external public debt service as percentage share of foreign exchange earnings and positive relationship for external debt stock as percentage of GDP on economic growth. But the negative effect of external debt service is much high. In short run only external debt service has negative effect and short run disequilibrium is corrected at high rate of speed. Granger causality analysis represents causal relationship from total external debt service payment to external debt stock. Forecasting value of GDP growth rate for 2011 is 6.1107 from Box-Jankin methodology.