To realize the process information sharing and three-dimensional annotation, a standardization description model for machining process information was proposed, which including three layers, natural language description layer, object oriented language description layer and symbolic language description layer. By extension the graphical symbol of surface texture, integrated with machining allowance, surface lay and direction, surface roughness, machining method and technical parameters, equipment, fixture, cutting tools, test information, and sequence number, a graphical symbol for three-dimensional machining process information was proposed. Then formulated the annotation specification of the graphical symbol, including annotation plane, position and orientation, associativity, indication of two or more machining step, restricted area and color using. Finally, a three-dimensional machining process planning system was developed, and a part machining process annotation was taken to illustrate the validity of the graphical symbol.