Based on the reduced two-fluid equations, the linear stability analysis of the drift-tearing mode(DTM) with thermal transport effect is performed and the parameter dependence of the growth rate is investigated. It is found that, when ω* ≫ γ0 holds, the DTM is destabilized by the effect of parallel thermal transport χ∥▽2T in the large limit of χ∥ and is unstable even in the range of Δ′ < 0. It is also found that there is the threshold value of χ∥ above which the diamagnetic drift frequency acts as destabilization of the DTM. The detail analysis of DTM with χ ∥ is now going on in terms of destabilzation mechanism in Δ′ < 0 and the threshold value. These issues will be reported in the conference.