We report on the temperature dependence of ferromagnetic resonance ͑FMR͒ measurements on NiFe/FeMn bilayer. This includes investigations about the angular distribution of the resonance, H R , and that of the linewidth, ⌬H. By considering the domain-wall formation model, the exchange-bias field, H EB,FMR , is derived from the FMR measurements. The disagreements observed at low temperature between these values and the ones obtained from superconducting quantum interference device measurements, H EB,SQUID , are discussed. We demonstrate that the negative line shift and the maximum of the linewidth of the FMR line are both perfectly interpreted through the slow-relaxer mechanism. This enabled us to elucidate the intriguing question about the yielding to different values of the exchange-bias anisotropy by both techniques.