Molecular photoswitch research has drawn much attention in the last century owing to its great potential in the development of smart materials. However, photoswitches suitable for constructing light-responsive luminescent materials remain limited, especially those involving triplet-state phosphorescence. Herein, we designed a novel molecular photoswitch based on the conformation transition of phenothiazine derivatives, minimizing steric hindrance (-CH3 > -Cl > -F) to regulate the conformation transition process while introducing a cyanobenzene acceptor to promote phosphorescence emission potential. When they were doped into a polymer matrix, varying photoswitch rates were achieved by incorporating different steric hindrance groups into phenothiazine or cyanobenzene groups, accompanied by photoresponsive room-temperature phosphorescence. This study is expected to greatly expand the diversity and applications of organic photoswitch molecules.