This disclosure provides a method for nonlinearly calibrating linear frequency modulation of an optical signal, an apparatus for nonlinearly calibrating linear frequency modulation of an optical signal, a computer-readable storage medium, and an electronic device. The method includes: in an ith frequency modulation cycle, obtaining a relationship between a modulation voltage signal Vi(t) input into a light source and an actual frequency signal fi(t) of an optical signal output by the light source, to obtain an actual association relationship fi(V) corresponding to the ith frequency modulation cycle, where i is a positive integer; based on a target frequency modulation signal fg(t) and the actual association relationship fi(V), determining a modulation voltage signal Vj(t) corresponding to a jth frequency modulation cycle, where j is i+1; and inputting a modulation voltage signal Vj(t) into the light source, to implement frequency modulation of the optical signal in the jth frequency modulation cycle.