A new calibration method of detectors based on the multimode spatial correlation of entangle photons which is generated from parametric-down-conversion is proposed and demonstrated experimentally. BBO nonlinear crystal is pumped by a continuous work ultraviolet 355 nm to generate entangle photons with wavelengths of 710 nm/710 nm at signal channel and 700 nm/720 nm at idle channel. The quantum efficiency is calibrated by taking the multimode correction method. The theory and calibration scheme of this novel method is presented and the system uncertainty is detailed analyzed. It is proved that the combined uncertainty of this new method is less than 4.7%. The approach presented is compared with the calibration result provided by the manufacturer, the relative difference is 10.3%, 10.2% at signal channel 12.9%, 8.95% at idle channel. The quantum efficiency of detector that doesn’t depend on time correlation measurement can be obtained by means of two branches of photons number statistics. The calibration results indicate its validity and rationality.