People　often　mix　superplasticizer　and　particulate　to　increase　the　density　of　high-concrete,　but　ignoring　the　effect　of　coarse　aggregate　gradation　on　concrete　strength.　Referring　to　several　Gradation　Theories,　this　paper　selects　the　coarse　aggregate　gradation　with　skeleton,　uses　uniform　design　method　to　test　the　compressive　strength　of　high-strength　concrete,　and　analyses　the　test　results.　It　can　be　known　from　the　test　results　of　7d　and　28d　concrete　specimen　that　the　concrete　strength　decreases　linearly　with　water-cement　ratio　and　sand　ratio;　The　7d＇s　concrete　strength　has　higher　variability　due　to　low　water-cement　ratio　with　superplasticizer;　The　coarse　aggregate　skeleton　is　interfered　by　the　increase　of　steel　slag　and　sand　rate,　and　the　concrete　strength　decreases　with　limited　cement　paste.　Furthermore,　the　steel　slag　with　less　than　30%　addition　has　little　effect　on　concrete　strength　and　it　can　increase　the　cement＇s　possibility　of　contacting　to　water,　and　reduce　the　amount　of　cement　without　lowering　the　concrete　strength.　The　influential　degree　on　the　compressive　strength　of　concrete　is　followed　by　ascending　sequence　of　steel　slag　content,　sand　ratio　and　water-cement.　©　(2013)　Trans　Tech　Publications,　Switzerland.