Abstract: A high performance liquid chromatography (HPLC) for the determination of five effective glycosides and an inductively coupled plasma mass spectrometry (ICP-MS) for the determination of trace elements in Radix Rehmanniae Praeparata were established to optimize the processing technology of Radix Rehmanniae Praeparata. The traditional wine-steaming process of Radix Rehmanniae Praeparata was used as a control, and the contents of five effective glycosides and trace elements were used as evaluation indexes to determine the optimal process for the different frequencies of Radix Rehmanniae Praeparata concoctions. The results showed that the content of Catalpol, Rehmannioside D, Leonuride, Acteoside, Isoacteoside as well as the content of trace elements of iron, zinc and copper were increased, while the content of harmful elements of cadmium and arsenic were reduced in Radix Rehmanniae Praeparata obtained by the "seven-steaming and seven-sun-drying" concocting process. Five kinds of effective glycosides and trace elements in Radix Rehmanniae Praeparata were accurately detected by HPLC and ICP-MS, respectively, and "seven-steaming and seven-drying" was determined as the best processing technology for Radix Rehmanniae Praeparata, which provided a scientific basis for the preparation of Radix Rehmanniae Praeparata.