Purpose: Performing precision equalization on the low-response detection units of electromagnetic calorimeter (ECAL), it is essential for precision energy measurements of Alpha Magnetic Spectrometer (AMS-02).Methods: Cosmic helium nuclei are used instead of protons to perform the equalization. During the equalization, temperature effects are analyzed and corrected to improve the accuracy.Results: The results of helium equalization are consistent with proton equalization, and the precision of helium equalization is about 1.5%.Conclusions: The precision of helium equalization is better than that of proton equalization, which provides a reliable alternative to ECAL on-orbit equalization.