Formation resistivity is a very important parameter influenced on oil and gas evaluation, and dual induction logging is a usual logging technology to measure the formation resistivity in horizontal well. As the formation boundaries are often unparallel in the actual logging, it should be concerned to the influence of unparallel boundary bed on dual induction logging response in horizontal well. Based on the 3D numerical mode-matching(NMM) method and through the forward modeling numerical analysis, this paper discussed the influence factors on dual induction logging response in horizontal well, such as dip angle of boundary bed, formation thickness, resistivity of surrounding rock and invaded area, etc. The results show that the unparallel boundary has certain effects on dual induction logging in horizontal well and the degree of influence is related to the dip angle of boundary bed, which can provide some theoretical references for correction of dual induction logging in horizontal well.