Pulse-burst　1064-nm　picosecond　azimuthal　polarization　beam　amplification　up　to　an　average　power　of　16.32　W　using　side-pumped　Nd:　YAG　amplifiers　has　been　demonstrated.　The　maximum　envelop　energy　as　much　as　16.32　mJ,　corresponding　to　a　power　amplification　factor　of　299.5%.　A　simple　criterion　was　defined　to　help　estimate　the　amount　of　depolarization　in　Nd:YAG　amplifier　stages.　The　degree　of　depolarization　of　the　beam　was　7.1%　and　the　beam　quality　was　measured　to　be　M-2　=　3.69.　The　reason　for　the　azimuthal　polarization　depolarization　and　beam　quality　degradation　were　explained　theoretically　and　experimentally　during　the　amplification　process.