Abstract: The disclosure provides a light-responsive aptamer for regulating the activity of a DNA polymerase. The DNA polymerase includes a G-quadruplex-binding peptide and a polymerase sequence; the polymerase sequence includes an active site; and the light-responsive aptamer includes an aptamer sequence and a photoactive linker connected to the aptamer sequence; the aptamer sequence includes a G-quadruplex-forming sequence and a substrate DNA sequence; the G-quadruplex-forming sequence forms a G-quadruplex, and the substrate DNA sequence folds to form a hairpin structure; the G-quadruplex-forming sequence binds to the G-quadruplex-binding peptide, and the substrate DNA binds to the active site of the DNA polymerase; in the presence of ultraviolet light irradiation (UV irradiation), the photoactive linker is broken, and the substrate DNA is detached from the active site of the DNA polymerase.