To obtain the subject monofilament low in thermal shrinkage force without lowering its alternate flexural strength, good in processability, and useful for technical cloths or wires, by incorporating a filament-forming polymer with a specific rubber and an aging resistor followed by melt spinning of the blend.

This monofilament is obtained by melt spinning of a blend composed of (A) 99-70wt.% of a polyamide, polyester of polypropylene, (B) 30-1wt.% of a maleic anhydride-modified polyethylene/polypropylene rubber and (C) an aging resistor stabilizer (e.g. a sterically hindered phenolic compound) at ≤3 (pref. 0.01-3)wt.% based on the total weight of the components A and B. This monofilament, which is good in processability during its processing into process felts or wires for use in lawn mowers, also enables the service life of technical cloths made thereof to be significantly prolonged.