The radiative recombination time (τr) was calculated for inhomogeneous polar InGaN QWs emitting in the green spectral range. These calculations were performed in the framework of a model where the τr is inversely proportional to the electron‐hole overlap integral. In order to simulate inhomogeneities in this model, it was assumed that the QW width, barrier widths and indium concentration vary with a Gaussian distribution where the nominal QW width, barrier widths and indium concentration correspond to the mean value in this distribution and their fluctuations correspond to the deviation from the main value. The τr was calculated for five thousands of randomly generated InGaN QWs and next the spectral map of PL decay was generated for the calculated τr which correspond to various QW regions. The obtained maps were compared with the measured maps of PL decay for InGaN QWs emitting in the green spectral range. It has been clearly shown that QW inhomogenities (i.e., QW width fluctuations and indium concentration fluctuations) lead to a spectral dispersion of the τr and the non‐exponential behavior of PL decay curves. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)