Gear integrated error technology was one of the worldwide leading technologies developed in China in the early 1970s and had been widely promoted and applied, which had made great contribution to the progress of China gear industry. However, the development and application of gear integrated error technology have entered a bottleneck period over the past 20 years. With the emergence of new technical conditions, some traditional problems of gear integrated error technology can be solved by these innovative solutions, which make the inherent advantages of high measurement efficiency and rich information about gear integrated error technology more prominent. The gear integrated error technology is expected to enter in a new period of rapid development. The development history and research status of gear integrated error technology are summarized. The difficulties and key problems in the elementary theory of the gear integrated error technology are analyzed. The feasible solutions, breakthrough directions and future research trends of the problems above are given, which provide a certain amount of reference and basis for the technology and theory of gear integrated error in the upcoming development.