Segregation in steel cast products is an internal defect that can be very harmful when slabs are rolled in heavy plate mills. Several mathematical models of segregation have been developed in previous works; all of them develop some equations to modelize segregation behavior. In this work it is intended to develop a model based on neural networks obtaining a deeper knowledge on this phenomenon. The first trials have been done with a variable selection based on the experience and previous knowledge on segregation. Further studies will include new variable selection and trials with other machine learning techniques such as genetic programming.