A wavelength calibration method, apparatus, and system is disclosed. The method includes: selecting sonic wavelengths from a plurality of wavelengths, and performing the following operations on a microring filter for each of the some wavelengths, to obtain sets of calibrated voltages of the some wavelengths: (1) adjusting thermal tuning power of multiple microrings by using one set of voltages, and obtaining multiple sets of voltages that enable monitored optical power to have an extreme value, and (2) using the multiple of sets of voltages as a reference, adjusting the thermal tuning power of the multiple microrings by using another set of voltages, and determining one of the sets of calibrated voltages, which enables the monitored optical power to converge, from the multiple sets of voltages; and then, obtaining, through calculation based on the sets of calibrated voltages of the some wavelengths, sets of calibrated voltages of other wavelengths.