Basalt filament is manufactured in such a manner that the fiber diameter can be controlled and the filament is not severed during the winding step. A network former and a glass modifier are formed and maintained with respect to basalt rock ore, and the crystallization and binding of basalt fiber are inhibited, the heat-resistance property of basalt fiber is greatly improved from the conventional 750 DEG C to 850 or 900 DEG C, and significant cost reduction is achieved over conventional products. The method includes the steps of: grinding basalt rock as a material; washing a resultant ground rock; melting the ground rock that has been washed; transforming a molten product into fiber; and drawing the fiber in an aligned manner, and winding it. The temperature of the molten product in the melting step is 1400 to 1650 DEG C, and log eta is 2.15 to 2.35dPas and preferably 2.2 to 2.3dPas, where eta is the viscosity of the molten product.