Abstract: The latest fruits of paleontology, magnetostratigraphy and chronology are adopted to make a fine classification on the Muling formation of Jixi group, by means of high-resolution sequence calculation and global sea level curve comparison. The forming time of Muling formation is determined in early Barremian-early Albian of the Early Cretaceous, with absolute time of 116-107 Ma. The main coal-bearing member in lower Muli formation was formed between 115 Ma and 111 Ma. The result provides a foundation of exact time for the high precision stratigraphic subdivision and coal-forming period in Eastern Heilongjiang Province.