This paper introduced a method of saving materials and energy through making small hollow blocks with the slag admixture in the lightweight aggregate concrete. Through orthogonal design, this paper took slag content, water binder ratio and admixture dosage into consideration and focused on influence of slag content on the physical and mechanical properties of lightweight aggregate concrete small hollow blocks. The results show that: when water binder ratio ，admixture dosage and curing system keep a fixed level, during the range of slag content 30%-40%, with the increase in slag content, the compressive and bending strength of small hollow block increased first and then decreased; water content and absorption and relative water moisture content decreased first and then increased; frost resistance increased then decreased; softening coefficient first increased and then decreased. When the slag content is 35%, the physical and mechanical properties of lightweight aggregate concrete small hollow block are the best, and all the indexes of physical and mechanical properties can meet the standard requirements non-bearing lightweight aggregate concrete hollow block. The curing system significantly affected the strength of the lightweight aggregate concrete small hollow block, and the block strength cured under the standard condition was higher than those under natural condition.