1. A method for color temperature correction in a portable terminal having a built-in camera, comprising the steps of: analyzing a captured image with histograms of red, green, blue, and gray channel; determining whether the histogram of the RGB channels and the histogram of the gray channel overlap over a predetermined percentage; measuring each color distribution average value of the RGB channels if the histogram of the RGB channels and the histogram of the gray channel overlap over a predetermined percentage; and performing a color temperature correction using the color distribution average value measured in each of the RGB channels on the captured image.