Circularly polarized photodetectors require chiral light absorption materials with high sensing efficiency and low costs. Here readily accessible point chirality has been introduced to dicyanostilbenes as the chiral source, facilitating remote chirality transfer to the π‐aromatic core by cooperative supramolecular polymerization. The single‐handed supramolecular polymers display powerful circularly polarized photodetection capability with a dissymmetry factor value as high as 0.83, superior to those of π‐conjugated small molecules and oligomers. Strong chiral amplification occurs between the enantiopure sergeants and the achiral soldiers. The resulting supramolecular copolymers exhibit comparable photodetection efficiency to those of the homopolymeric ones, with a 90 % decrease in the enantiopure compound consumption. Therefore, cooperative supramolecular polymerization provides an effective yet economical avenue toward circularly polarized photodetection applications.