To obtain a wiry composite material with its core material as linear material bundle free from any flaw or breakage, free from any defects due to malimpregnation and/or voids or the like, therefore capable of sufficiently exhibiting the performance inherent therein.

The subject method for melt impregnation comprises the following process: a linear material bundle is continuously introduced via an inlet sealed part provided on the bottom of an impregnation tank containing a molten matrix material and impregnated with the matrix material, the linear material bundle thus impregnated is squeezed at a squeezing section furnished in the vicinity of the level height of the molten matrix material and then continuously withdrawn from the impregnation tank via an outlet sealed part provided above the level of the matrix material; wherein the inlet sealed part, the squeezing section and the outlet sealed part are disposed along an identical straight line, and the interior of the impregnation tank is pressurized.