Abstract: This paper provides an insight into the present situation and the latest development of pipeline corrosion inspection technologies of the world. The foreign advanced intelligent pigs used for inside pipeline corrosion inspection are described. After analyzing the technological gap between the advanced countries and our country ,it becomes clear that using the intelligent pigs to detect the pipeline corrosion has become the trend of the world. Combining with the problems existed in application of the foreign pigs, some suggestions of the study on intelligent pigs are proposed.