In order to explore the way of building materials utilization of secondary aluminum ash sintered slag, the influence and mechanism of different content of sintered slag on the mechanical and shrinkage properties of C50, C60 and C70 concrete were studied. The results show that the compressive strength of C50 and C60 concrete is slightly higher than that of unadded sintered slag reference specimen when the content of sintered slag is 15% (account for total fine aggregate mass), while for C70 concrete, the compressive strength of high-strength concrete specimens with different sintered slag content is lower than that of unadded sintered slag reference specimen. When the sintered slag content is in the range of 10%~15%, the reduction of compressive strength is the lowest. The effect of low content sintered slag on peak strain, ultimate strain, elastic modulus and Poisson ratio of high-strength concrete is not obvious, but the effect of high content sintered slag is significant, and the effect is the greatest on higher strength grade concrete. When the sintered slag content is 15%, the total shrinkage rate and self-shrinkage rate of high-strength concrete are the lowest, among which the total shrinkage of C50, C60 and C70 concrete decreases by 29.05%, 22.17% and 27.88%, and the self-shrinkage rate decreases by 15.24%, 26.52% and 30.56%, respectively, compared with the reference group without sintered slag. Therefore, when the content of sintered slag is 15%, the internal curing effect of high-strength concrete is equivalent to the negative effect of low self-strength, so that high-strength concrete can obtain the appropriate compressive strength and the lowest shrinkage rate.