The invention discloses a three-stage operational amplifier suitable for a wide capacitive load range. The three-stage operational amplifier comprises a first backward gain stage, a forward gain stage, a second backward gain stage, a compensation capacitor, a feed-forward trans-conductance amplification stage and a cascode compensation stage, wherein the first backward gain stage, the forward gain stage and the second backward gain stage are connected in series in sequence; the two ends of the compensation capacitor are connected with an output end of the first backward gain stage and an output end of the second backward gain stage respectively; the cascode compensation stage is connected in parallel with a capacitor; an output end of the cascode compensation stage is connected with the output end of the first backward gain stage, and an input end of the cascode compensation stage is connected with the output end of the second backward gain stage; and an output end of the feed-forward trans-conductance amplification stage is connected with the output end of the second backward gain stage, and an input end of the feed-forward trans-conductance amplification stage is connected with an input end of the forward gain stage. Through adoption of the operational amplifier, a larger bandwidth and a larger phase margin are realized; the slew rates of large signals and the response speeds of small signals are increased; the compensation capacitance is reduced; and the chip manufacturing cost is lowered.