To improve the sensitivity of quantum ring infrared photodetector(QRIP) and restrain the dark current of QRIP,a QRIP with multiplication region,quantum ring absorption layer and Al0.3Ga0.7As/In0.1Ga0.9As double barrier structure is designed.The numerical model of the QRIP is built based on the 3D Schrodinger equation of the quantum ring.The electrical and optical characteristics are simulated.The simulation results show that the responsivity of the detector reaches 40 A/W,and the normalized detectivity reaches 2×1010 cm·Hz1/2/W.