Let K/k be a finite abelian CM-extension and T a suitable finite set of finite primes of k. In this paper, we determine the Fitting ideal of the minus component of the T -ray class group of K, except for the 2-component, assuming the validity of the equivariant Tamagawa number conjecture. As an application, we give a necessary and sufficient condition for the Stickelberger element to lie in that Fitting ideal.