The petroleum geological characteristics of Artala sag are systematically summarized, and the stratigraphic sequence, tectonic evolution, depositional system and hydrocarbon accumulation conditions are analyzed. Through the study of hydrocarbon accumulation conditions, the main controlling factors in each formation are determined and hydrocarbon enrichment rule is summarized. Based on a brief comparison between Erlian Basin and other sags, the distinctive characteristics of this sag in the aspects of tectonic and deposition are summed up. The representative characteristics such as later tectonic inversion, depositional systemdeveloping widely in steep slope and syndepositional anticline development in the Erlian Basin are pointed out.