The invention discloses an unblocking method for a blocked pipe cleaner of a subsea mixture transportation pipeline with the high wax content. The method comprises the following steps that firstly, the blocked position of the pipe cleaner is determined; secondly, the tail end of the subsea pipeline gets into a continuous pipeline to a blockage section, and a medium circulation channel is established; thirdly, residual liquid in the section of subsea pipeline is discharged; fourthly, a cleaning reagent is injected into the tail end of the subsea pipeline through a beating and pressing device; fifthly, the cleaning reagent is added and then subjected to standing to be immersed for 5 hours; sixthly, gas lift returning liquid of gas is injected, the saturability of the dissolved cleaning reagent is detected, and the dissolved wax amount is judged; seventhly, a blind plate capable of being detonated is additionally arranged, and the residual liquid in the subsea pipeline continues to be discharged; and eighthly, the inlet end of the subsea pipeline is pressurized to push the blocked pipe cleaner out. The unblocking method has the beneficial effects that wax blockages in the subsea pipeline can be efficiently removed, safe and rapid unblocking is achieved, and damage to the subsea pipeline due to unblocking through a traditional method and generated environment risks are avoided.