The pulsed laser performances of a-axis YAP crystal doped with 10at%, 20at% Er3+ ion have been studied experimentally. In our experimental condition, it is possible to excite simultaneously three spectral lines at 2.7110μm, 2.7299μm and 2.7950μm. The output energy and the time characteristics are given for these spectral lines. 240mJ output energy has been obtained at 2.7μm range from a 6.25×78mm Er3+:YAP rod with a threshold energy of about 10 J.