Chemical synthesis is a powerful tool for human being as it provides many useful products, especially those that do not exist or only exist in a small quantity in nature. Since it is often hard to design and visualize the reactions of organic synthesis, retrosynthesis is often used to achieve a desired product. This review is an introduction of the concepts of retrosynthetic analysis and how it can be established, including the basic steps and strategies. It also discuss the guiding principles of retrosynthesis (simplification, complexity, yield) along with some possible problems and coping strategies in the analyses, including functional group disconnections, fine tuning, and illogical disconnections.