Objective To observe the features of new tubers and mother tubers in different growth stages of Corydalis yanhusuo. Methods We traced the tuber formation process of Corydalis yanhusuo, as well as the growth of new tubers and mother tubers, by real-time observation and paraffin sectioning. Results The new tubers produced by the underground stem grew from the stem nodes of mother plant, and their formation needed some necessary conditions. The new tubers were also reproduced from the mother tubers; the mother tubers degenerated into the periderm of the reproduced tubers and finally fell off a couple of months later. It was more common for cultivars to produce twin tubers and multiple tubers compared with wild varieties. Tubers contained fluorescent alkaloids. Conclusion New tubers are formed in a variety of ways. The periderm from degenerated mother tubers can protect reproduced tubers. Cultivars have a strong ability of asexual reproduction. Fluorescence alkaloids are distributed homogeneously in the mature tubers of Corydalis yanhusuo, and no aggregation is observed.