Based　on　the　Langevin　noise　approach,　a　full　quantum　theory　of　radiation　in　laser　plasma　is　explored,　where　the　laser　intensity　is　limited　to　the　range　of　10(10)　W/cm(2)　to　10(12)　W/cm(2)　and　the　plasma　is　considered　as　a　homogeneous　dielectric　background.　By　numerical　calculation,　the　results　show　that　the　radiation　is　generated　from　the　resonance　of　the　plasma　and　the　emitted　rate　of　photons　depends　on　the　angular　relation　between　the　directions　of　radiation　fields　and　the　motion　of　the　unbounded　free　electrons.　In　addition,　the　photons　are　more　easily　created　under　the　lower　collision　frequency.