|This study compared the effects of FC Incorporating on improvement of BS mortar for which DRA was used with NFA, The results can be summarized as follows. First, Flow, in case less than FC 40%, showed a tendency similar to Plain, regardless of the type of fine aggregates, but in case of FC 60%, DRA increased and, in case of NFA, it tended to decrease. Air Contents increased as FC Incorporating increases regardless of the type of fine aggregates. In case of plain mortar for which FC was not replaced in compressive and flexural strength of only BS was used, the strength of NFA rarely tended to be strong even though 28 days elapsed, but DRA is increase of strength to some extent caused by latent hydraulic reaction of BS by alkali and, according to FC incorporating, showed the highest compressive at FC 20% regardless of the type of fine aggregates, so that it could be known the percentage(20%) is the optimum admixture ratio. In the meantime, with regard to compressive strength relationship between BS mortar, for which, DRA and NFA were used, it could be known that generally BS mortar for which NFA was used showed highest compressive, but the difference was within 25%, and the two value became similar around 15 MPa.