In this study, a flexible interphase than matrix resin is studied. The fabrication method of unidirectional CFRP laminates with flexible fiber/matrix interphase has been established. The influence of the flexible interphase thickness on the flexural modulus and strength are experimentally investigated. The influence on the vibration properties are also investigated. It has been concluded that the flexible interphase with the optimized thickness could improve both the static and dynamic properties.