An optical power equalization method, which is applied to a flexible grid reconfigurable optical add drop multiplexer, Flex ROADM, system and comprises: judging, according to an optical power monitoring result and an optical power control target value of each optical channel, whether optical power equalization needs to be performed on each optical channel, each optical channel comprising sub-carriers; and when the judgement result is that the optical power equalization needs to be performed on each optical channel, performing equalization on the optical power of each optical channel and the optical power of each sub-carrier in optical channel according to the optical power monitoring result; wherein performing equalization on the optical power of each optical channel and the optical power of each sub-carrier in each optical channel according to the optical power monitoring result comprises: performing equalization on the optical power of each optical channel and the optical power of each sub-carrier in each optical channel according to the optical power monitoring result by means of backward control and/or forward control, wherein the backward control refers to controlling an attenuation parameter of an upstream flexible grid optical power equalization executor, and the forward control refers to controlling an attenuation parameter of a downstream flexible grid optical power equalization executor. judging, according to an optical power monitoring result and an optical power control target value of each optical channel, whether optical power equalization needs to be performed on each optical channel, each optical channel comprising sub-carriers; and when the judgement result is that the optical power equalization needs to be performed on each optical channel, performing equalization on the optical power of each optical channel and the optical power of each sub-carrier in optical channel according to the optical power monitoring result; wherein performing equalization on the optical power of each optical channel and the optical power of each sub-carrier in each optical channel according to the optical power monitoring result comprises: performing equalization on the optical power of each optical channel and the optical power of each sub-carrier in each optical channel according to the optical power monitoring result by means of backward control and/or forward control, wherein the backward control refers to controlling an attenuation parameter of an upstream flexible grid optical power equalization executor, and the forward control refers to controlling an attenuation parameter of a downstream flexible grid optical power equalization executor. performing equalization on the optical power of each optical channel and the optical power of each sub-carrier in each optical channel according to the optical power monitoring result by means of backward control and/or forward control, wherein the backward control refers to controlling an attenuation parameter of an upstream flexible grid optical power equalization executor, and the forward control refers to controlling an attenuation parameter of a downstream flexible grid optical power equalization executor.