  The proton-neutron interaction is investigated by solving the Schrodinger
equation, where a Yukawa type of potential with one pion exchanging between the
proton and the neutron is assumed. Since the deutron is the unique bound state
of the proton-neutron system, the coupling constant is fixed according to the
binding energy of the deutron. The scattering process of the proton and the
neutron is studied when the outgoing wave condition is taken into account, and
two proton-neutron resonance states are obtained by solving the Schrodinger
equation, which lie at $1905-i13$MeV and $2150-i342$MeV on the complex energy
plane, respectively. It is no doubt that the calculation results would give
some hints on the experimental research on the proton-neutron interaction in
future.
