The aim of this article is to introduce the roles and mechanisms of the JAK2/STAT3 pathway in various cardiovascular diseases, such as myocardial fibrosis, cardiac hypertrophy, atherosclerosis, myocardial infarction, and myocardial ischemiareperfusion. In addition, the effects of phytochemical ingredients and different natural plants, mainly traditional Chinese medicines, on the regulation of different cardiovascular diseases via the JAK2/STAT3 pathway are discussed. Surprisingly, the JAK2 pathway has dual roles in different cardiovascular diseases. Future research should focus on the dual regulatory effects of different phytochemical ingredients and natural plants on JAK2 to pave the way for their use in clinical trials.