The invention discloses a high-stability flyback direct current-direct current (DC-DC) converter. According to the converter, a voltage feedback loop and a current feedback loop are adopted in flyback topology, so that the transient response of a converter device is accelerated. A novel frequency compensation circuit is also adopted. The frequency compensation circuit mainly comprises an error amplifier, a Miller capacitance control unit and a dynamic zero control unit. According to the Miller capacitance control unit, a large compensation capacitor in the traditional dominant pole compensation can be replaced by a small compensation capacitor, so that the area is saved, and the transient response of the system is improved. According to the dynamic zero control unit, the introduced zero point can well offset the first non-dominant pole of the system under the condition that the output has fluctuation, and the stability of the system is guaranteed. According to the DC-DC converter, a compensation resistor and a compensation capacitor can be integrated to a chip, internal compensation is realized, and the area of the chip is saved; meanwhile, the circuit structure is simple, the reliability is high, the phase margin can be 90 degrees, and the stability of the system is high.