The present disclosure provides a global shutter CMOS pixel circuit and its image capturing method. The global shutter CMOS pixel circuit comprising a power supply unit, a pixel signal generating unit, a signal sampling and holding unit and a signal outputting unit. An output of the pixel signal generating unit is connected to an input of the signal sampling and holding unit. An output of the signal sampling and holding unit is connected to an input of the signal outputting unit. The output signal of the pixel and the photo-generated current are set to a logarithmic relationship, which effectively increases the signal dynamic range. Therefore, image signal transmission with high speed and high dynamic range can be achieved simultaneously. Furthermore, the pixels in the present disclosure can eliminate the process variations, which increases the consistency of the pixels.