The present invention provides a color mixing lens which can improve color reproducibility, be made slim and adjust an emission pattern; and a liquid crystal display device having the same. The color mixing lens includes a light receiving portion having at least two light emission diodes positioned at a side for emitting color lights different from each other and light receiving recesses for placing the light emission diodes therein respectively, a color mixing portion formed on the light receiving portion for mixing the lights from the light emission diodes into a white color light, and a light emission portion formed on the color mixing portion for emitting the white light from the color mixing portion through a side thereof.