Abstract: Experiments with fibre Bragg grating were done to study the residual stresses distribution in composites structure during the autoclave curing process. From results of experiments, residual stresses development and distribution in thickness direction and planar have been obtained. And then the mechanism and influence of residual stresses on cure-induced deformation for composites structure were studied. The results show that the mismatch between composites and mold induce the strain gradient in thickness direction. The strain close to the mold is more than that away from the mold. And then the strain will cause deformation of composites structure after curing process, and the deformation in fibre direction is dominating.