Abstract: In order to study the early (28 d) strength and distribution of pore microstructure characteristics of slag cement block under different curing temperature , the water cement ratio of the cement block was 0.24, doped with different amounts of slag as admixture to the cement block , the cement blocks were maintained at minus three degrees Celsius and twenty degrees Celsius for twenty -eight days respectively , measure the compressive strength of cement block , analysis of the early pore structure of cement block by using the pore structure analyzer , then through the pore structure of cement block calculate the actual strength of cement blocke , comparative analysis of its law .The results show that:at the same amount of slag, the early compressive strength of the cement blocks at minus three degrees Celsius curing temperature is decreased significantly than at twenty degrees Celsius curing temperature , hardened cement air containing volume becomes small , the bubbles spacing factor and average pore chord length increase, pore coarsening seriously;With the increase of slag amount , the early compressive strength of cement block is decreased , hardened cement air containing volume increases , the bubbles spacing factor and average pore chord length increase ,the bubbles spacing factor , average pore chord length and early compressive strength of cement blocks at minus three degrees Celsius curing temperature change trend is more obviously than at twenty degrees Celsius .

Key words: cement block;curing temperature;content of slag;compressive strength;pore structure