To provide monofilament for fishing lines, having uniform scratch resistance to abrasion both in the direction of fiber axis and in the transverse direction crossing the fiber axis at right angle, which is excellent in resistance to root hooking during actual fishing and whose knot strength and knot elongation are improved; and also to provide a method for producing the same, and the fishing line.

The monofilament for fishing line is made by forming a coating layer of polyamide or polyester thermoplastic hot-melt adhesive on the surface of thermoplastic resin monofilament. The monofilament has a knot strength of 5.0 cN/dtex or more, and a knot elongation of 15-40%. The monofilament also has a tension strength retention of 75% or more after a scratch test in the transverse direction.