Microwave irradiation-induced synthesis of nanomaterials offers large-scale fabrication by in-situ decomposition of organo-metallic complexes through a variety of solvents. But there are limited attempts to fabricate them using a solvent-free environment. In the present work, we have reported successfully pyrolysis of ferric acetylacetonate complex to produce iron oxide using mesoporous graphite (MG) under microwave irradiation without assistance of solvent. The two-step synthesis consists of the preparation of mesoporous graphite using mild conditions of Hummer’s method and its composite with ferric oxides was done by heating mesoporous graphite with ferric acetylacetonate in a domestic microwave oven. The preliminary magnetic behavior of in-situ synthesized mesoporous graphite (MG) composite with mixed ferric oxides was studied. The room temperature magnetic behavior of the as-prepared composite exhibited saturation magnetization of 11.27 emu-g-1. The Formation of α-Fe2O3 and γ-Fe2O3 along with particle size distribution and dispersion was evaluated through detailed structural characterization. Our study shows mesoporous graphite acts not only as a substrate but also as a microwave receptor. This can extend the avenues of existing carbonaceous materials in converting microwave energy into thermal energy.