We report a 12 × 12 In0.53Ga0.47As-In0.52Al0.48As avalanche photodiode (APD) array. The mean breakdown voltage of the APD was 57.9 V and the standard deviation was less than 0.1 V. The mean dark current was ∼2 and ∼300 nA, and the standard deviation was ∼0.19 and ∼60 nA at unity gain (Vbias = 13.5 V) and at 90% of the breakdown voltage, respectively. External quantum efficiency was above 40% in the wavelength range from 1.0 to 1.6 μm. It was ∼57% and ∼45% at 1.3 and 1.55 μm, respectively. A bandwidth of 13 GHz was achieved at low gain.