A calibration method for a coherent optical module, wherein the method comprises: obtaining a first curve relationship and a second curve relationship, wherein the first curve relationship represents a relationship between a power-gain monitoring voltage and optical power of a receiver of the coherent optical module in an optical power range of the receiver of the coherent optical module, the power-gain monitoring voltage being used to measure a voltage amplitude output by an integrated coherent receiver of the coherent optical module, and the second curve relationship represents a relationship between a target setting voltage and the optical power of the receiver of the coherent optical module in the optical power range of the receiver of the coherent optical module, the target setting voltage being used for adjusting the voltage amplitude output by the integrated coherent receiver of the coherent optical module; determining first optical power based on the first curve relationship and the second curve relationship, wherein the first optical power is used to divide the optical power range of the receiver into two ranges, a first range of which is greater than a lower limit value of the optical power range of the receiver and less than the first optical power, and a second range of which is greater than or equal to the first optical power and less than an upper limit value of the optical power range of the receiver; determining a calibration mode of the coherent optical module based on the first optical power, wherein the calibration mode comprises: in a case that the optical power of the receiver of the coherent optical module is in the first range, calibrating the coherent optical module by using the first curve relationship; and in a case that the optical power of the receiver of the coherent optical module is in the second range, calibrating the coherent optical module by using the second curve relationship. obtaining a first curve relationship and a second curve relationship, wherein the first curve relationship represents a relationship between a power-gain monitoring voltage and optical power of a receiver of the coherent optical module in an optical power range of the receiver of the coherent optical module, the power-gain monitoring voltage being used to measure a voltage amplitude output by an integrated coherent receiver of the coherent optical module, and the second curve relationship represents a relationship between a target setting voltage and the optical power of the receiver of the coherent optical module in the optical power range of the receiver of the coherent optical module, the target setting voltage being used for adjusting the voltage amplitude output by the integrated coherent receiver of the coherent optical module; determining first optical power based on the first curve relationship and the second curve relationship, wherein the first optical power is used to divide the optical power range of the receiver into two ranges, a first range of which is greater than a lower limit value of the optical power range of the receiver and less than the first optical power, and a second range of which is greater than or equal to the first optical power and less than an upper limit value of the optical power range of the receiver; determining a calibration mode of the coherent optical module based on the first optical power, wherein the calibration mode comprises: in a case that the optical power of the receiver of the coherent optical module is in the first range, calibrating the coherent optical module by using the first curve relationship; and in a case that the optical power of the receiver of the coherent optical module is in the second range, calibrating the coherent optical module by using the second curve relationship.