A method of producing a unidirectional fiber-reinforced composite material by covering bundles of an inorganic fiber having unidirectionally high elasticity and high strength with a wire-like, foil-like or knit-like material which is the same as, or different from, a matrix metal and is capable of being molten and diffused into said matrix metal, to thereby form a fiber body having an optional shape, volume and fiber density; placing the resulting fiber body in an appropriate location within a mold; pouring a molten matrix metal into said mold; and squeeze casting said molten matrix metal along with the fiber body to form the unidirectionally fiber-reinforced composite material while causing said covering material to melt and diffuse under heat of said molten matrix metal into the latter.