This article examines the international crude oil trade and the international petroleum trade through econometric analysis and complex network analysis, focusing on the aspects of the driving forces and resistances for the oil trade and competitive or cooperative relationships among countries. The crude oil trade network and the petroleum trade network are constructed. Positional and role analysis reveals that countries can be divided into five positions in the crude oil trade network and twenty-five positions in the petroleum trade network. The relationships among countries within or between positions are discussed and recognized as competitive or cooperative. The bilateral oil trade analysis shows that various factors within countries have influence on bilateral trade volume. The analysis also implies that restrictions on trade partner selection due to geographical resistance forces neighboring oil-importing countries to choose similar oil-exporting countries, which corresponds with the results of the complex network analysis. The complex network analysis shows that the countries in the same position belong to the same region. Furthermore, the analysis results imply that the diversification in petroleum exporting countries reduces the supply disruption risk for importing countries.