The development of stimuli‐responsive artificial H+/Cl‐ ion channels, capable of specifically disturbing the intracellular ion homeostasis of cancer cells, presents an intriguing opportunity for achieving high selectivity in cancer therapy. Herein, we describe a novel family of non‐covalently stapled self‐assembled artificial channels activatable by biocompatible visible light at 442 nm, which enables the co‐transport of H+/Cl‐ across the membrane with H+/Cl‐ transport selectivity of 6.0. Upon photoirradiation of the caged C4F‐L for 10 min, 90% of ion transport efficiency can be restored, giving rise to a 10.5‐fold enhancement in cytotoxicity against human colorectal cancer cells (IC50 = 8.5 μM). The mechanism underlying cancer cell death mediated by the H+/Cl‐ channels involves the activation of the caspase 9 apoptosis pathway as well as the scarcely reported disruption of the autophagic processes. In the absence of photoirradiation, C4F‐L exhibits minimal toxicity towards normal intestine cells, even at a concentration of 200 μM.