We recently reported a new lasing dye, trans‐4‐[p‐(N‐ethyl‐N‐hydroxylethylamino)styryl]‐N‐methylpyridinium tetraphenylborate (ASPT), which has also been shown to possess a strong two‐photon absorption (TPA) and subsequent frequency upconversion fluorescence behavior when excited with near infrared laser radiation. Based on the TPA mechanism, a highly efficient optical limiting performance has been demonstrated in a 2 cm long ASPT‐doped epoxy rod pumped with 1.06 &mgr;mQ‐switched laser pulses at 50–250 MW/cm2intensity levels. The measured nonlinear absorption coefficient reached 6 cm/GW for the tested sample of dopant concentrationd0=4×10−3M/L. The molecular TPA cross section of ASPT in the epoxy matrix is estimated as &sgr;2=2.5×10−18cm4/GW or &sgr;2′=4.7×10−46cm4/photon/s, respectively. Two‐photon pumped cavity lasing is also observed in an ASPT‐doped polymer rod. ©1995 American Institute of Physics.