A new class AB operational amplifier was proposed to solve the problems of low slew rate and low gain-bandwidth product of traditional operational amplifiers for low power applications such as the Internet of Things. The current reuse technology based on differential pair transistors was proposed, which reuses the differential current generated by the input transistors. As a result, the output current of the circuit is enhanced, and the slew rate, gain-bandwidth product and DC gain are improved significantly. Moreover, differential input stages with class-AB operation and local common-mode feedback circuit are combined. As a result, the dynamic current of the output stage of the operational amplifier will not be restricted by the static current, and the larger dynamic current can be obtained under the smaller static current. The operational amplifiers is designed with a 180 nm CMOS process. For a 70 pF load capacitance, the simulation results show that the positive and negative slew rates are 23.55 V/μs and -31.47 V/μs, respectively, the gain-bandwidth product is 2.38 MHz, the DC gain is 63 dB, and the static power consumption is only 23 μW. The results show that, compared with the traditional class AB operational amplifier, the proposed circuit achieves higher slew rate, higher gain-bandwidth product and higher DC gain under lower power consumption. The proposed circuit is suitable for low power circuits and systems such as analog-to-digital converter and power management.