Emission cross sections of a Nd stoichiometric laser crystal LiNdP4O12at 1.048 &mgr;m were measured by a direct absorption method and the conventional spectroscopic method. The largest effective‐emission cross section was determined to be &sgr;beff= (1.7±0.2) ×10−19cm2by these two methods. Emission cross sections of NaNdP4O12, KNdP4O12and LiNd0.1Ln0.9P4O12(Ln=Gd, La) were also determined by the conventional spectroscopic method. The radiative lifetime of LiNdP4O12was calculated from the fluorescence spectra and the quantum efficiency of LiNdP4O12was found to be 0.34.