The invention discloses a fine design method for an oil-gas pipeline engineering power cable. The method comprises the following steps of: managing engineering projects, drawing an oil and gas pipeline engineering power plane graph which comprises drawing equipment, a cable path, an interruption symbol, a protection pipe and the like; automatically calculating a cable laying path by a system according to equipment and paths drawn in the plane graph, the interruption symbols and connected cable numbers of the given equipment, generating accurate cable length and path numbers passed by the cablelength after the system automatically calculates the cable laying path, and finally generating exportable cable tables, material tables and equipment tables in Excel formats. The method has the beneficial effects that by means of the method, the design period can be effectively shortened, the cutting accuracy is improved, measurement errors of designers are reduced, the labor intensity of the designers is reduced, and the design efficiency is improved; moreover, verification and matching of the power cable and the matched pipe fitting can be automatically completed, and intelligent calculation and verification functions are provided, so that the design quality is improved.