Two main mooring methods, fluke anchor and suction anchor, used in Catenary Anchor Leg Mooring (CALM) are focused on. Their applicable environmental conditions and rules are analyzed by theoretical calculations. The installation process and action mechanism are presented in the form of pictures and tables. Their advantages and disadvantages in practical applications are summarized and compared. An auxiliary analysis software is designed using Visual Basic and the reliability of the program is verified by engineering cases, which fulfills high requirements on the safety, stability and economic applicability of the mooring systems proposed by the projects.