Manufacturing method of polarizing film and manufacturing apparatus of polarizing film

An objective of the present invention is to provide a manufacturing method of polarizing film capable of stably and continuously manufacturing a polarizing film while suppressing adhesion of precipitates deposited from a treatment liquid used for wet treatment of a polyvinyl alcohol-based resin film to the above-mentioned film. The manufacturing method of polarizing film of the present invention comprises: a step of immersing a polyvinyl alcohol-based resin film in a dyeing treatment tank containing a dyeing treatment liquid; a step of immersing the polyvinyl alcohol-based resin film after the step of immersing in the dyeing treatment tank in a crosslinking treatment tank containing a crosslinking treatment liquid; a step of obtaining a particle-containing liquid containing particles comprising a polyvinyl alcohol-based resin by applying a shearing force to at least a part of the crosslinking treatment liquid withdrawn from the crosslinking treatment liquid in the crosslinking treatment tank; and a step of re