The　operating　condition　of　a　cw　simultaneous　dual-wavelength　Nd:YAG　laser　for　both　F-4(3/2)-I-4(9/2)　(quasi-three-level　system)　and　F-4(3/2)-I-4(11/2)　(four-level　system)　transitions　is　studied.　According　to　this　condition,　the　cw　simultaneous　dual-wavelength　at　1.06mum　and　946　nn　in　Nd:YAG　crystal　has　been　realized　experimentally　through　an　adaptive　coating　design　of　the　cavity　mirrors.　A　total　power　output　of　2.5W　of　the　dual-wavelength　at　946nm　and　1.06mum　has　been　achieved　with　an　optical　conversion　efficiency　14.3%.　The　experimental　results　are　in　good　agreement　with　the　theoretical　analysis.