By considering the fermionic realization of G/H coset models, we show that the partition function for the U(1)/U(1) model defines a topological quantum field theory and coincides with that of a two-dimensional Abelian BF system. In the non-Abelian case, we prove the topological character of G/G coset models by explicit computation, also finding a natural extension of two-dimensional BF systems with non-Abelian symmetry.Facultad de Ciencias Exactas