The invention discloses a voltage ripple detection circuit, and the circuit comprises a conversion circuit which is used for converting a to-be-detected signal into a pulse signal; a first filtering circuit which is used for filtering the pulse signal to generate a reference signal; and a subtraction circuit which is used for carrying out the subtraction of the to-be-detected signal and the reference signal so as to obtain a ripple voltage signal. Therefore, the circuit achieves the detection of voltage ripples when equipment is in operation.