Bulk Molding Compound is a popular engineering FRP and is used in Automobile and Electric instrument. Durability of BMC for machinery material was researched but today the application of this material has been developed in more hard circumstance. In the situation, this material was sometimes exposed by some cyclic loading-speeds and hard circumstances such as water absorption and high temperature. In this report, the effect of water absorption and frequency on bending strength and bending fatigue strength has been researched considering the distribution of mechanical properties. The fatigue fracture mechanisms were studied by observation method. From these result, it was found that crack initiation and propagation was mainly depended on delamination around glass fiber bundle.