Based on field survey and lab analysis, the authors emphasized the dissolution in the process of stalagmite depositing. According to mechanism of dissolution, dissolution can be sorted into three types: physical dissolution, chemical dissolution and biological dissolution. With the study of field observations and stalagmite longitudinal profiles from South China, it shows that dissolution is ubiquitous phenomena which runs through the speleothem forming process. In the field, physical dissolution and chemical dissolution lead to erosion pits on the top of stalagmites. Biological dissolution forms crusts of weathering that wrap around stalagmites.