In this article the real equilibrium exchange rate in 1993-I quarter of 2003 and in sub-periods 1993-1998 and 1999-I quarter of 2003 was estimated. The sub-periods were chosen in view of different exchange rate policy and, in general, monetary policy. The estimations concerned various versions of the purchasing power parity thesis and the macroeconomic balance approach worked out and developed by the International Monetary Fund. Both methods, though quite different, give convergent results in the second sub-period. Deviations of the nominal effective exchange rate of zloty from the equilibrium exchange rate are relatively small; only between 2001-IInd quarter of 2002 the overvaluation of the exchange rate of zloty approached 5-8%. Deviations of the exchange rate of zloty from the bilateral exchange rates (PLN/USD and EUR/USD) are higher and depend on the changes of the cross-rate EUR/USD.