The recently discovered superconductor YFe2Ge2 (Tc about 1.8K) has the same crystal structure as 122 iron-based superconductors, with no static magnetic order be reported. However, our recent triple-axis experiment revealed strong spin fluctuations at Q=(1,0,1), corresponding to a stripe antiferromagnetic correlation consistent with in the 122 systems. Thus, there comes a contradiction between the similarity to 122 systems and the rather low Tc in YFe2Ge2. In order to have further understanding of the superconducting mechanism of this compound, we propose an experiment on the high energy spin fluctuations in YFe2Ge2, which will enable us to determine the effective Hamiltonian and to make a direct comparison with the 122 iron-based superconductors. Our experiment will shed some lights on the mechanism of pairing and the origin of low Tc. We request a 7 days' beam time for MAPS.