Neutron resonance spin-echo (NRSE) phenomena was studied experimentally and theoretically. The particular case, when resonance condition had been fulfilled, was considered. The spin precessions were produced in a classical manner and by neutron resonance and both were combined as two arms of spin-echo machine. A spin-echo signal of the precision produced by the NRSE arm was recorded. The limiting cases of neutron spin-flip probability and initial polarization condition were considered as key parameters of the system. The experiments showed the linear spin state superposition principle of neutron particle waves and the interference as a result of that. The phases of the SE signals observed were determined by up to eight interfering waves.