The high-performance control of permanent magnet synchronous motors hinges on precise rotor position information. However, traditional mechanical sensors are plagued by high costs, large dimensions, and low reliability. As a result, position sensorless control technology has emerged and is becoming a research hotspot in the field of motor control. This article comprehensively reviews the existing position sensorless control technologies for permanent magnet synchronous motors. First, the fundamental principles of classical methods based on the motor’s fundamental wave model and saliency effect are analyzed in detail. Second, the advantages, disadvantages, and applicable scenarios of various position sensorless control methods are summarized. Finally, the key issues that need to be addressed in future research are pointed out.