According to the calculation method of planned working hour for installation work package of pipe outfitting workpiece, the key points of automatic calculation of planned working hour based on the detailed specification are proposed. The specification and attribute data of pipe outfitting workpiece are extracted, the working hour standard database is established, the correction factors are determined, the automatic calculation of planned working hour is realized, and the revision of working hour standard database is made with the working hour efficiency analysis. The practical application in the related enterprises proves that the automatic calculation of planned working hour for installation work package of pipe outfitting workpiece based on the detailed specification is of practicality.