PURPOSE: To provide a treating method intended to prevent aromatic polyamide fiber breakages in their caulking under high compressive force in fitting fitments after hose forming when aromatic polyamide fibers are to be applied as cords for high-pressure hose reinforcement.

CONSTITUTION: Aromatic polyamide fibers are treated, in advance, with a treating agent containing a polyepoxide compound, and twisted under the relationship for the first twist: 0.1≤K≤1.5 (K=(T×D1/2)/2874; K: twist multiplier; T: number of twists/m; D: denier) followed by twisting a plurality of the resultant twisted cords under the relationship for ply twist: 0.8≤K≤4.0 in the opposite or same direction. Thence, the resulting cords are imparted with the second treating agent containing resorcin-formalin-latex (RFL).