A　Nd:GdPO4　single　crystal　with　dimensions　of　31　×　13　×　10　mm3　was　grown　by　the　top-seeded　solution　method.　Polarized　absorption　and　fluorescence　spectra　of　the　crystal　were　measured　at　room　temperature　and　analyzed　based　on　the　Judd-Ofelt　theory.　The　effects　of　the　energy　transfer　and　energy　migration　processes　on　the　fluorescence　lifetime　of　the　4F3/2　multiplet　of　Nd3+　were　discussed,　as　well　as　the　concentration-dependent　fluorescence　quenching　effect　was　also　investigated.　End-pumped　by　a　quasi-continuous-wave　790　nm　laser　diode,　a　1060　nm　laser　with　a　maximum　output　peak　power　of　1.12　W　and　a　slope　efficiency　of　21.9%　was　obtained　in　a　Nd:GdPO4　crystal　at　an　absorbed　pump　peak　power　of　5.39　W.　©　2021