The surface energy of FOX-7 and the soaking effect of fluoropolymer FOX-7 were studied in comparison with TATB by using the contact angles and Young-Good-Girifalco-Fowkes(YGGF) equation.The calculation results show the interfacial energy and interaction of FOX-7 with fluoropolymer are close to that of TATB. Fluoropolymers have good soaking effect on FOX-7 and TATB, and the effect on TATB is better than that on FOX-7. FOX-7 has strong alkalescence that offers electron easily on the acid-base interaction. The particle of FOX-7 with two fluoropolymers (F₂₆₀₃ and F₂₆₄₂) were studied by SEM as well. The results show the soaking of FOX-7/F₂₆₀₃ is much better than that of FOX-7/F₂₆₄₂ on particle scale,however,it can be expected that the fluoropolymer can make the almost same effect on FOX-7 and TATB on the whole.