A MICRO-channel heat exchanger reactor with different MICRO-BAFFLE shapes has been studied numerically. Governing equations were solved base on the finite volume method with FLUENT software. In the upper section of the reactor oxidation reaction of methanol occurred, and in the lower section steam reforming of methanol took place. Two sections were separated by a solid part which played the role of a heat exchanger and transferred heat from the oxidation reaction to the steam reforming section. In addition to the straight MICRO-channel, other types of MICRO-channel with different MICRO-BAFFLE shapes on both sides of the solid section were studied. MICRO-BAFFLEs are thought to act as static mixers, inducing further mixing and improving the convective heat transfer coefficients which eventually expedite heat transfer which increases conversion efficiency. Also, the hydrogen yield obtained by a rectangular MICRO-BAFFLE is 17% higher, on average, than that obtained with by a straight configuration. Five different MICRO-BAFFLEs with Rectangular, Triangular, Triangular90, Trapezoidal and Trapezoidal 90 shapes were studied and the highest conversion efficiency for the MICRO-BAFFLEs was achieved in the Trapezoidal shape.