As one of strengthening methods for damaged reinforced concrete bridge slabs, this study has been carried out to develop an alternative method by using methyl meta acrilate (MMA) resin concrete with carbon fiber sheets (CFS), in which strengthening and waterproof properties are expected. The test results both in static and fatigue loadings using the full-scale beam specimen that have been carried out under the loading of negative moment are reported and discussed. Main results from this study are as follows: 1) The MMA resin concrete has an excellent bonding property up to the failure like as the epoxy resin one. 2) the bonding length for CFS is required at least the length between the bent-up bars. 3) for the fatigue design of the strengthened slab, the S-N relationship was obtained.