To provide a processing method/a processing system of waste resin which can keep a good work environment with reduced equipment troubles, in turning waste resin into fuel.

The process to turn the waste resin into fuel comprises (1) a screening process S10 to remove a foreign substance from the waste resin separately recovered at a waste disposal site etc. and clean deposits sticking to the waste resin, (2) a crushing process S20 to crush the waste resin processed by the screening process S10, (3) a dehydrating process S30 to dehydrate the waste resin crushed by the crushing process S20, (4) a classifying process S40 to introduce the waste resin dehydrated by the dehydrating process S30 into a classifying machine and classify the waste resin as a coarse particle portion and a fine particle portion, and (5) a fuel mixing process S50 to mix the fine particle portion of the waste resin classified by the classifying process S40.