Carrier lifetime has been measured by the luminescence decay of a 1.3‐&mgr;m‐InGaAsP layer excited by a mode locked YAG laser at 1.06 &mgr;m. The measurements have been done as a function of excitation intensity for nearly three orders of magnitude of carrier concentration (4×1016–2×1019cm−3) and for different temperatures (between 32 and 346 K). At low and moderate carrier density, the lifetime &tgr; follows the variation with excitation of the theoretical radiative lifetime. At high carrier density (above 1018cm−3) the carrier decay rate increases more rapidly than the radiative one and around room temperature this can be accounted for by an additional recombination mechanism whose variation with excitation is typical of an Auger process. The Auger coefficient (Ca=2.6×10−29cm6 s−1) does not vary with temperature within experimental uncertainty. This suggests that though Auger recombination is for a large part responsible for the lowT0value of 1.3‐&mgr;m InGaAsP lasers, the temperature dependence of the Auger coefficient does not contribute to it.