With　the　self-compacting　concrete　as　new　concrete,　the　shear　experiment　of　new　and　old　concrete　is　conducted　by　the　push-out　shear　test　in　order　to　study　the　bond-slip　relationship　between　the　self-compacting　concrete　(different　strength)　and　old　concrete.　After　loading,　the　strain　of　new　concrete　is　measured　along　the　bonding　length.　With　the　distribution　of　strain　and　stress　in　concrete,　the　part　bond　stress-slip　curves　of　new　or　old　concrete　are　deduced.　The　results　show　that　the　curves　of　bonding　strength　are　developed　with　three　stages.　The　slope　of　the　curves　is　minor　near　the　free　side.　The　stress　and　slip　of　load　side　also　increase　faster　than　that　of　the　other　sides.　Based　on　the　regression　analysis,　the　constitutive　relation　of　part　bond　stress-slip　is　suggested.　It　can　be　taken　as　the　reference　to　the　structural　design.　2　tabs,　6　figs,　10　refs.