In　this　paper,　we　proposed　a　joint　design　scheme　between　sphere　decoding　and　user　scheduling　for　multiuser　MIMO　uplink　system.　This　is　a　cross　layer　design　scheme　which　adopt　the　channel　quality　information　based　on　user　scheduling　to　reduced　the　search　radius　of　sphere　detector,　it　leads　the　better　bit　error　ratio　performance　and　low　complexity　than　conventional　sphere　detection　with　fixed　search　radius.