The renormalized Yukawa theory in the two-dimensional space-time is considered.
The existence of asymptotical limits of the creation-annihilation operators is proved.
It is also shown that the commutation relations of these asymptotical operators with
the total Hamiltonian are of the same form as those of the usual creation-annihilation
operators with the free Hamiltonian. This provides us with some information about the
spectrum of the total Hamiltonian.