Arrhythmia is a common life-threatening cardiovascular disorder. Potassium channels play a crucial role in cardiac electrophysiology, and their dysfunction is closely associated with the occurrence and development of arrhythmia. Traditional Chinese medicine (TCM) has a long-standing history in treating various diseases, including arrhythmia and offers a rich source of compounds for anti-arrhythmic drugs. To provide in-depth new insights for the development of novel anti-arrhythmic therapies this review delves into TCM’s effects on potassium channels through multiple ways, including the direct interaction between the active ingredients contained and potassium channels, regulation of the expression of related genes and proteins, intervention in intracellular signaling pathways, and exertion of antioxidant and anti-inflammatory effects. With continued efforts in standardization, research, and integration with Western medicine, TCM is playing an increasingly important role in the treatment of arrhythmia and provides novel options for patients worldwide. Phenomics and pharmacophenomics as well as the artificial intelligence-based GPCR ligand screening system may provide new paradigms and platforms for discovering and developing more antiarrhythmic drugs.