Abstract: Low cost technology for composites is the key issue in the present development of composite materials. However the processing time estimation is the central objective in the manufacturing cost estimation. This paper provides a processing time estimation model based on the process of manufacturing composite waved beams by autoclave molding. This paper clearly identifies the method of defining the parameters and variables estimated，which is applied to the time estimation model. The experimental data is fitted by the least squares algorithm. It shows that the model is preferable to estimate manufacturing composite waved beams. Moreover，modifying the time constant for single short wave-length beam and the velocity constant for single long wave-length beam could get a result with little difference from the practical data. So，it is verified that this manufacturing time estimation model could realize accurate time estimating for different configuration designs.