The 5.8, 3.0 and 1.2 MeV Li ions were used to study the MBEIn0.25Ga0.75As/GaAs (100) sample. Ion channeling angular scans about[100] and [110] axes were carried out in the (100) plane.It is found that in the case of 5.8 MeV, the critical angle of the epilayer is almost the same as that of the substrate and the angle misalignment between them is 0.90° for axis [110] , corresponding to the misfit of sample being 1.62%, in good agreement with theoretical calculation. In the 3.0 MeV case, serious asymmetry have been observed in RBS/Channeling angular scan; in the 1.2 MeV case, the angular misalignment is reduced to 0.50° and the critical channeling angle of substrate is increased significantly. We have studied and discussed the physical mechanism of these anomalous phenomena in detail, and present a good interpretation of the experimental results.