Flexural strength of concrete and its growth with different cement mortar matrix and reinforced by different coarse aggregate including crushed limestone,steel aggregate,mortar and expanded shale were studied by experiment.The research results show that the coarse aggregate and cement mortar matrix have significant influence on flexural strength of concrete;when the strength and modulus of elasticity of coarse aggregate match to those of cement mortar matrix,it has remarkable effect on flexural strength of concrete by increasing aggregate strength,but when the strength and modulus of elasticity of coarse aggregate is too much high,the flexural strength of concrete will decrease owing to the stress concentration;the effect of enhancing cement mortar matrix compressive strength on improving concrete flexural strength is not prominent either when aggregate strength is lower.The differences in compressive strength and modulus of elasticity between coarse aggregate and cement mortar matrix influence the flexural strength of concrete and its growth significantly;only if the strength and modulus of elasticity of coarse aggregate match those of cement mortar matrix,the better effect could be achieved.