Activated by alkaline activator prepared by sodium metasilicate and sodium hydroxide, the metakaolin fly ash based engineered geopolymer composites(MFA EGC) was prepared using fly ash as the main raw material and metakaolin as auxiliary material, and uniaxial tensile property of MFA EGC were explored. The results show that MFA EGC has good multi cracking behavior after uniaxial direct tensile test. The distribution of cracks is uniform, and the crack spacing is in the range of 25mm, and the average width of residual cracks is about 25μm. The tensile strength for the optimum proportion at 3, 7, 28d is 32, 37, 38MPa respectively, and the ultimate tensile strain can be up to 68%, 64% and 52% respectively, and initial crack strength is 14, 15, 19MPa respectively. The order of influence of factors on the tensile properties is as follows:curing temperature>metakaolin content>PVA fiber content. Through the three point bending and the single crack tensile test, it is shown that the calculated pseudo strain hardening(PSH) index is consistent with the trend of ultimate tensile strain by the uniaxial direct tensile test, which can well explain its high ductility.