The deep Web has many challenges to be solved. Among them is schema matching. In this paper, we build a conceptual connection between the schema matching problem SMP and the fuzzy constraint optimization problem FCOP. In particular, we propose the use of the fuzzy constraint optimization problem as a framework to model and formalize the schema matching problem. By formalizing the SMP as a FCOP, we gain many benefits. First, we could express it as a combinatorial optimization problem with a set of soft constraints which are able to cope with uncertainty in schema matching. Second, the actual algorithm solution becomes independent of the concrete graph model, allowing us to change the model without affecting the algorithm by introducing a l of abstraction. Moreover, we could discover complex matches easily. Finally, we could make a trade-off between schema matching performance aspects. Key words: Schema matching, Constraint programming, Fuzzy constraints, Objective functions.