The experimental realization of a Heisenberg-Kitaev model on the honeycomb lattice has been a major topic in a condensed matter physics, because the model predict a novel quantum spin liquid ground state and unusual magnetic phases induced by spin-orbit coupling and electronic correlation. The newly discovered alpha-RuCl3 has strong indications that it lies in proximate to a Kitaev spin liquid phase. Our preliminary inelastic neutron scattering result at MERLIN reveals a broad continuum and an abnormal dispersion of spin excitation at low energy transfer region but detailed nature is not conclusive. Using relatively good resolution and flux of LET beamline, we will clarify novel magnetism related to the Heisenberg-Kitaev model.