Disclosed are a lens shading compensation apparatus and a lens shading compensation method in an image sensor that compensate the difference in signal amplitude according to the position of pixels to preserve the quality of a primitive image. The lens shading compensation apparatus includes a pixel value analyzing part, an auto exposure value setting part, a central pixel detecting part, a table generating part, a pixel location calculating part, a mask image generating part and a compensation part. The above apparatus and method perform a color interpolation individually for red, green and blue, and then compensate a lens shading image for each color in accordance with its characteristics. Also the above apparatus and method can analyze and compensate a lens shading phenomenon without considering other colors or being interrupted by other colors.