We have undertaken a multidisciplinary study of the thermal decomposition of Murchison CM2 carbonaceous chondrite as an analog to metamorphic process that may have occurred on carbonaceous asteroids. The pre- and post-heated Murchison powders were analyzed using X-ray diffraction, thermal and evolved gas analysis, visible-near-infrared spectroscopy, microto nanoscale analyses included scanning and transmission electron microscopy. Mineralogical analyses of the unheated Murchison samples identified fine-grained serpentine, rounded Mg-rich serpentine (chrysotile-type), platy Fe-rich serpentine (cronstedtite-type), tochilinite, tochilinite-cronstedtite intergrowths, olivine, pyroxene, iron-nickel sulfides, magnetite, potassium iron-nickel sulfide, calcite, gypsum, apatite, Cr-bearing spinel, and chromite. The tochilinite shows the contorted morphology, mainly showing (002) lattice fringes of ~5.4 Å spacing and the identification of a new twinning relationship on the (032) plane. In response to thermal effects, serpentine group minerals are converted into mixtures of sub-μm olivine and pyroxene grains with similar Mg/Mg+Fe ratios as the precursor. Tochilinite breakdown forms troilite, magnetite, and minor Fe-Ni metal aggregates via amorphization. The thermal processing of Murchison carbonaceous chondrite produces distinctive micron and submicron structures that correspond to the breakdown of key minerals. These findings will be useful for understanding the thermal history of carbonaceous asteroids and for analyzing samples returned from ongoing missions to primitive asteroids (101955) Bennu and (162173) Ryugu.