This paper aims to see whether the EU enlargement was associated with positive, negative or non-effect on Poland’s economic growth. To be able to answer this question we use the econometric method, time series with data from 1997 to 2018. The determinants of economic growth in Poland are set of variables selected based on previous studies in the same field of our study. The findings of this study shows that there is no significant relationship between economic growth and the EU enlargement in the case of Poland. The result of our regressions did not demonstrate similar result of previous study which we believe are due to the small number of observation used in our models. However, if our findings reflect the economic reality in Poland, then this can open up a new strand of further research.