Abstract:The number of jacket removal projects is increasing in recent years. The bearing capacity of jacket lifting point is one of the most important factors to determine the removal method. We select a seven-year in-service jacket in Bohai Bay of China as an example. The marine growth thickness of the jacket is about 300 mm， which is about 10 times of normal marine growth thickness. The removal weight of the jacket is more than twice of the install weight of the jacket， and the trunnion （the lifting point type of the jacket) has already appeared pitting corrosion because it is in the tidal zone. So the trunnion needs to be strengthened. But the modification is difficult because the internal space of the trunnion is small. The thought and method of transformation of the trunnion are discussed detailedly. The way to improve the bearing capacity， which can effectively solve the defects of the original structure， is put forward. This research provides a design train of thought for the jacket removal projects in the future.