PURPOSE: To obtain a polyamide yarn product especially effective as polyamide yarn product treated with finishing oil such as mop free from an unpleasant smell in unpacking after long-term preservation in a packaged state by providing polyamide yarn with a nonvolatile acid or acidic salt.

CONSTITUTION: Polyamide yarn is immersed in an aqueous solution containing a nonvolatile acid or acidic salt such as acidic sodium metaphosphate, tetrapolyphosphoric acid, sodium tetrapolyphosphate, tripolyphosphoric acid, sodium tripolyphosphate or acidic sodium pyrophosphate, dehydrated and dried.