Abstract: Well TS3 is the first discovery well in the deep Ordovician of Tahe oil field. Commercial oils were tested in the Yingshan Formation of the Middle-Lower Ordovician. The physical characteristics of oils from TS3 well block are similar to those from nearby near-surface reservoirs, which both are super heavy oils with high freezing point, high sulfur content, high wax content and high viscosity. The n-alkane series are complete with a variable hump in the chromatographic baselines and widespread 25-norhopane series. The carbon isotopes of saturate hydrocarbons and asphaltenes are partly reversed. These features indicate that the reservoirs in TS3 well block underwent at least 2 periods of hydrocarbon filling and forming. In addition, oil inclusions with yellow, yellow-green and blue fluorescence and gas inclusions were tested in calcites of the Yingshan Formation reservoir. The homogenization temperature of inclusions suggests three periods of hydrocarbon filling:Late Caledonian-Early Hercynian, Late Hercynian and Late Himalayan. Combined with physical properties (super heavy oils) and maturity (mature oils) of the present oils, the first period of oil and gas filling was dominant in the TS3 well block.