A method for regulating optical power, wherein a new service wavelength is added in an optical network and there is no existing service wavelength in the optical network, the method comprising: determining a first power attenuation value of a power regulation unit related to the new service wavelength and in the optical network according to a path of the new service wavelength and a structure of the optical network; and calculating a performance parameter of a channel corresponding to the new service wavelength according to the first power attenuation value, wherein the performance parameter comprises an optical signal to noise ratio; determining whether the performance parameter of the channel corresponding to the new service wavelength meets a preset tolerance requirement and flatness requirement; and regulating a power attenuation value of the power regulation unit related to the new service wavelength to the first power attenuation value if a judgment result is yes; wherein the calculating the performance parameter of the channel corresponding to the new service wavelength according to the first power attenuation value comprises: obtaining optical power of the channel corresponding to the new service wavelength according to the first power attenuation value, and calculating the optical signal to noise ratio of the channel corresponding to the new service wavelength according to the optical power as well as a gain and a noise figure of an optical amplifier in the optical network; and characterized in that the determining whether the performance parameter meets the preset tolerance requirement and flatness requirement comprises: determining whether the optical signal to noise ratio meets a preset tolerance requirement of the optical signal to noise ratio and flatness requirement of the optical signal to noise ratio. determining a first power attenuation value of a power regulation unit related to the new service wavelength and in the optical network according to a path of the new service wavelength and a structure of the optical network; and calculating a performance parameter of a channel corresponding to the new service wavelength according to the first power attenuation value, wherein the performance parameter comprises an optical signal to noise ratio; determining whether the performance parameter of the channel corresponding to the new service wavelength meets a preset tolerance requirement and flatness requirement; and regulating a power attenuation value of the power regulation unit related to the new service wavelength to the first power attenuation value if a judgment result is yes; wherein the calculating the performance parameter of the channel corresponding to the new service wavelength according to the first power attenuation value comprises: obtaining optical power of the channel corresponding to the new service wavelength according to the first power attenuation value, and calculating the optical signal to noise ratio of the channel corresponding to the new service wavelength according to the optical power as well as a gain and a noise figure of an optical amplifier in the optical network; and characterized in that the determining whether the performance parameter meets the preset tolerance requirement and flatness requirement comprises: determining whether the optical signal to noise ratio meets a preset tolerance requirement of the optical signal to noise ratio and flatness requirement of the optical signal to noise ratio.