By using photon pairs generated from photonic crystal fiber, whose wavelengths can be continuously tuned from 750 nm～880 nm and 1 310 nm～1 620 nm, perform efficiency calibration for a single-photon detector (SPD) at multiple wavelengths covering three telecommands of O, C, and L we detected in the experiment. This method can be used for calibrating SPDs at any arbitrary wavelength in these three bands.