The invention discloses an environment-friendly low-drying-shrinkage crack-resistant casting waste sand concrete which is formed by mixing the following components in parts by weight: 330-370 parts of cement, 40-80 parts of rice hull ash, 700-780 parts of fine aggregate (formed by screening and mixing casting waste sand and river sand), 1080-1200 parts of coarse aggregate (macadam), 6-9 parts of shrinkage reducing agent, 3.5-5.5 parts of water reducing agent and 125-180 parts of water. The strength level of the environment-friendly low-drying-shrinkage crack-resistant casting waste sand concrete is C45-C55, the 7d drying shrinkage value is 75-100*10<-6>, the 28d drying shrinkage value is 200-250*10<-6>, the 90d drying shrinkage value is 260-300*10<-6>, and the drying shrinkage value trends to be stable; and the early crack resistance is Grade L-V. The environment-friendly low-drying-shrinkage crack-resistant casting waste sand concrete implements high-added-value recycling of the casting waste sand in concrete, and thus, has favorable environment-friendly effect. The fine aggregate, which is formed by screening and mixing the casting waste sand and river sand, effectively improves the grain size distribution of the aggregate. The rice hull ash, shrinkage reducing agent and other components are doped, thereby lowering the drying shrinkage value of the concrete and obviously enhancing the crack resistance from the angle of solid-liquid-phase optimum design.