The article takes up a comparative analysis of labour markets in Poland and in the EU Member States, and presents the expected impact of EU membership on the Polish labour market. Poland’s accession to the EU comes in a period characterised by a difficult situation on the Polish labour market (high and sustained unemployment, obsolete structure of employment). EU membership should be used to support the national policy in the field of employment and unemployment. The impact of EU membership on situation on the Polish labour market depends on the time-span of the analysis. In a short-term perspective (two-three years) the effects of factors adversely affecting the labour market situation (trade deficit, accelerated structural change and reallocation of labour force, implementation of technological progress and labour productivity growth) may dominate over the effects of factors acting towards improvement of the situation on that market (negative balance of foreign migrations, increased inflow of foreign direct investment, transfer of funds from the EU to Poland, programmes for improvement of labour force mobility). In the medium and long term the strength of impact of both groups of factors should be reversed, hence a favourable influence of accession on the labour market situation in Poland can be expected.