The automotive torque converter is a complex turbomachine used to transfer power smoothly from an engine to a transmission. Its hydrodynamic design technology has been advanced very much during the past few years. A review of technologies for developing the torque converter was presented. In this paper, the technologies in the torque converter were divided into four parts: one-dimensional analysis, experimental study, numerical study, and new design method of the torque converter. In order to provide useful guidances to the torque converter designer, numerous papers published previously were incited and summarized briefly in this paper.