A　Dy3+　:Na2La4(WO4)(7)　crystal　was　grown　successfully　by　the　Czochraski　method,　its　spectroscopic　properties　were　investigated　in　detail.　The　radiative　transition　probabilities,　fluorescence　branching　ratios,　and　radiative　lifetime　of　Dy3+　ions　were　obtained　based　on　the　Judd-Ofelt　theory.　The　absorption　cross　sections　at　454　nm　are　1.1　x　10(-21)　cm(2)　and　0.75　x　10(-21)　cm(2)　for　sigma-polarization　and　pi-polarization,　respectively.　The　stimulated　emission　cross　sections　at　574　nm　is　1.64　x　10(-20)　cm(2)　for　pi-polarization,　and　1.79　x　10(-20)　cm(2)　for　sigma-polarization.　The　fluorescence　lifetime　of　the　F-4(9/2)　energy　level　is　218　mu　s.　The　results　show　that　Dy3+　:Na2La4(WO4)(7)　crystal　is　very　suitable　for　commercial　450　nm　blue　laser　diodes　pumping,　and　is　a　promising　yellow　laser　material.