The state of polarization (SOP) of optical lightwave in fiber is very sensitive to the external events. Based on this phenomenon, the polarization time domain reflectometer (POTDR) can be used as a distributed sensing means for the detection of fiber pressing, bending, and vibration, etc. However, SOP of optical lightwave at a specific position is dependent to its previous status. That means the first disturbance nearest to the input end is usually fused with subsequent disturbances, which makes the POTDR method difficult to detect multi-disturbances. In this paper, research progress of multi-disturbances detection by POTDR was reviewed. Existing POTDR techniques like analyzing spectrum method, resolving local birefringence method and special sensing fiber method were introduced and analyzed.