Disclosed are a pixel array, an image sensor including the same, and a method of driving the same. In a WDR (Wide Dynamic Range) pixel employing a storage region (FD node) including a varactor, a reset voltage, which is less than a voltage applied to a reset transistor according to the related art, that is, a partial reset voltage is applied to the reset transistor to read out a reset signal level for a CDS (Correlated Double Sampling) operation, thereby adjusting the operating voltage range of the storage region. The operating voltage range of the storage region is shifted into a range suitable for remarkably varying the capacitance of the varactor, thereby expanding the dynamic range.