The invention belongs to the technical field of an electronic circuit, and relates to a COT control mode based offset voltage canceling circuit. The canceling circuit adopts an on-chip compensation technology; the potential information of SW is subjected to filtering processing to obtain a sawtooth wave which comprises direct current information and inductive current information; the direct current component is obtained by the circuit; then the alternating current component is extracted by subtraction through a subtraction circuit to obtain the required information of the ripple wave which is homodromous with the inductive current; next, the ripple wave and the feedback signal VFB are added through a ripple wave superposition circuit so as to ensure that the output capacitor ripple wave with the lagged phase position is weaker than the compensated ripple wave, so that the stable operation of the system is realized; and meanwhile, the repeated parameter design for the conventional off-chip ripple wave compensation circuit under different applications can be avoided, so that the applicable range of the offset voltage canceling circuit is expanded.