Abstract: Erlianhaote Hegenshan ophiolite belt is the largest exposed area of Late Paleozoic ophiolite in the eastern part of the Central Asian Orogenic Belt. It was once considered to be the suture zone of the last collision between the North China Craton and Siberian Plate, and there is still controversy in its tectonic attributes. The newly identified ophiolitic mélange in Ma'anshan area of Inner Mongolia is located in the eastern part of Xingmeng Orogenic Belt and is the eastern extension of the Erlianhaote-Hegenshan ophiolite belt. The discovery of the ophiolitic mélange fills the gap of the middle section of the Erlianhaote-Hegenshan-Heihe suture zone and provides new evidence for the evolution of Paleo-Asian Ocean tectonic domain. It was found that the mélange is composed of blocks and matrix through petrographic, geochemical and chronological studies of Ma'anshan ophiolitic mélange. The blocks are serpentinized peridotite, peridotite, diabase, basalt, high-magnesium andesite, andesite and rhyolite, and the matrix is mainly turbidite. The serpentinized peridotite has the characteristics of supra-subduction zone (SSZ) type ophiolite, and the diabase has the characteristics of SSZ tectonic background genesis. The basalt has the characteristics of (enriched mid-ocean ridge basult E-MORB) and island arc basalt, indicating that it was formed in a back-arc basin environment. The zircon U-Pb age (344.4±1.4) Ma of the diabase in Ma'anshan ophiolitic mélange is similar to the age obtained by previous researchers from Hegenshan ophiolite, confirming the existence of a subduction zone (suture zone) in this area, which is of great significance for the determination of the regional tectonic framework.