The invention provides an auxiliary material to be used in shape machining which brings about reduction in machining time, can give shape-machined workpieses not lowered in the shape quality, and has a relatively low manufacturing cost; a machining process with the same; and a process for the production thereof. The auxiliary material consists of tungsten alloy particles (1) which consist of 80 to 98% by mass of tungsten, nickel, at least one metal selected from among iron, copper, and cobalt, and unavoidable impurities and have the maximum diameter of 0.1 to 5.0mm and a specific surface areaof 0.02m<2>/g or below. A workpiece (30) is shape-machined by rotating a container (100) holding the tungsten alloy particles (1, 10), a workpiece (30), and an abrasive (20) therein. The tungsten alloy particles (1) are produced by a process of converting granulated powder into spherical particles by agitating the powder at a temperature higher than the softening point of the organic binder and then cooling it.