Understanding the inhibition mechanism of coal dust explosions is of great significance for the development of high-efficiency inhibitors and effective protection against explosion accidents. In this study, a novel phosphorus-containing composite PA@NH2-MCM41 was synthesized. The pyrolysis characteristics and the products of coal, coal/PA@NH2-MCM41, and PA@NH2-MCM41 were analyzed using in-situ pyrolysis time-of-flight mass spectrometry (in-situ Py-TOF-MS) and TG-DSC. The results show that the addition of PA@NH2-MCM41 can significantly reduce the content of light gases and organic volatiles released from coal pyrolysis. P-containing species are intensively released at 200–350 ℃. The pyrolysis components of PA@NH2-MCM41 mainly include [(HO)2PO]2O, PO(OH)3, and HOPO2, etc. These P-containing species can effectively terminate the chain reaction by combining H and OH radicals. In addition, PA@NH2-MCM41 has the potential to facilitate the formation of dense carbon layers of coal dust particles to hinder the pyrolysis and ignition of coal dust.