A 10 m center-spacing infrared readout circuit with 2×2 pixel binning function is introduced. This circuit combines the characteristics of high resolution and high frame rate, and can meet the requirements of both long-distance search and short-distance tracking and recognition application modes. Before pixel binning, the array specification of the readout circuit is 1280×1024 with a pixel center-spacing of 10 m and high spatial resolution, suitable for short-distance tracking and recognition mode. In the pixel binning mode, the array specification changes to 640×512, pixel center-spacing changes to 20 m, and the sensitivity is high, which can be used in long-distance search mode. In addition, the proposed circuit adopts a serial input control method and has functions such as integrate then read (ITR)/integrate while read (IWR) working mode switching, 4/8 channels selectability, flipping and power consumption control. This circuit is designed with GF 018 m process. The simulation results show that the achieved maximum frame frequency by the readout circuit is doubled in the pixel binning mode.