The　magnetocaloric　effect　of　Gd5Si2Ge2　alloys　under　heat　treatment　conditions　are　investigated　in　low　magnetic　fields.　The　magnetocaloric　effect　(MCE)　is　studied　by　measuring　magnetic　entropy　change　(Delta　S-M)　and　adiabatic　temperature　change　(Delta　T-ad)　in　a　magnetic　field　of　1.5　T　using　a　vibrating　sample　magnetometer　(VSM)　and　a　home-made　magnetocaloric　effect　measuring　apparatus,　respectively.　The　maximum　Delta　S-M　of　the　alloys　increases　by　200%　from　4.38　to　13.32　J　kg(-1)　K-1,　the　maximum　Delta　T-ad　increases　by　105%　from　1.9　to　3.9　K　when　compared　to　the　as-cast　due　to　the　homogeneous　composition　distribution　and　microstructure,　while　the　magnetic　ordering　temperature　is　slightly　reduced.　These　results　indicate　that　the　annealed　Gd5Si2Ge2　compounds　are　promising　as　high-performance　magnetic　refrigerants　working　room　temperature　in　relatively　low　magnetic　fields.