  We study spinon excitations of the integrable spin-1 (Fateev-Zamolodchikov;
FZ) chain and their relation to the hidden supersymmetry. Using the notion of
the supercharges earlier introduced to the spin chains, which change the system
length by one, we found that they nontrivially act on one of two kinds of the
degrees of freedom for the FZ chain. Their actions were obtained to be the same
as those of the supercharges defined on the supersymmetric sine-Gordon model,
the low-energy effective field theory of the FZ chain. Moreover, we construct
the eigenstates which are invariant under the supersymmetric Hamiltonian given
as the anti-commutator of the supercharges.
