Abstract: Tectonic coal is the product of strong tectonic compression and shear actions,and its crystalline structure perhaps records the tectonic features. In this paper,the microcrystal structure the organic matter evolution of badly twisted tectonic coal and its symbiotic un-tectonic coal were investigated by means of coal structure analytical method ( such as XRD,NMR,GC / MS and so on). Combined with the result of coal deformation-metamorphism feature and the power basis of forming tectonic coal,the confined-space oriented growth mechanism of coal microcrystal is tentatively proposed. The main points of the mechanism include:During forming tectonic coal,the system changed from a closed mode into an open one because of fracture structure,microfractures and cleavage in coal seam,then tectonic coal de- lamination became the confined spaces of coal microcrystal growth;Tectonic stress,gravity and adsorption were the driving forces for coal microcrystal oriented growth;Being confined-space and orientation binding,the growths and ar- rangements of coal microcrystallines tended to lie low like that of lamellar crystals,in the meanwhile,coal polymers reached the steady state through self-adjusting molecular conformations and chain arrangements. The results are useful for studying the coal structure evolution and physial-chemical mechanism of forming tectonic coal.