A 74-species reduced mechanism and a 94-species skeletal mechanism for bio-butanol oxidation were obtained from a 234-species detailed mechanism using an integrated reduction method involving directed relation graph (DRG), DRG-related and computational singular perturbation (CSP) + quasi-steady-state approximation (QSSA) methods. Firstly, the skeletal mechanism with 94 species and 497 reactions was derived by comparing the DRG and DRG-related methods. Then, 112 unimportant reactions were identified and eliminated through the CSP importance index method, and the final skeletal mechanism with 94 species and 385 reactions was generated. Finally, a reduced mechanism with 74 species and 70 step reactions was derived by using the CSP + QSSA method to identify and eliminate 20 QSS species. Simulation results of the 94-species skeletal mechanism and the 74-species reduced mechanism show good agreement with that of the detailed mechanism for different phenomena such as ignition, extinction, laminar flame speed and homogeneous charge compression ignition combustion.