Abstract:Under the background of “the Chinese continental scientific drilling project location and drilling test” in China, the article reviews and summarizes the great achievements and problems of drilling engineering of Russia СГ-3 ultra deep well. Based on the rethinking on the experience and lessons, some issues are discussed, which should be paid attention in future ultradeep scientific drilling project in China, such as scientific target and engineering management, scientific location selection, well deviation control and new drilling achievements, the related conclusion are presented.