Abstract: The forming environments of the pormo-carboniferous seams in North and South Huaihe may be divided into two types: peat platform and peat swamp.In the light of the depositional environments of the undercying sediments, they may be classified into some subtypes.In different forming environments of a seams, coal mass, quality, roof, floor, water medium and pertings are different. Vartically and horizontally, a same seam could be tormed in different environments, and different environments could be converted each other.