Abstract: In order to study the output characteristics of diode-end-pumped Nd: YAP laser operating at 1341.4nm,the thermal focal lengths of end-pumped Nd:YAP laser were calculated and measured, and the output results of lasers with plane-plane and plano-concave resonators were compared respectively.Making use of plane-concave resonator with the coupler transmission of 2.4% and plane-plane cavity with the coupler transmission of 2.6%,3.15W and 2.86W linearly polarized laser radiation at 1341.4 nm were obtained,respectively,corresponding optical slope efficiency of 18.4% and 17.5%.The results show that Nd:YAP laser crystal owns the potential advantages on 1.3μm laser.