An image color adjusting method and an electronic device thereof are provided. The image color adjusting method includes following steps: obtaining multiple groups of first pixel data of an image in a first color space, and performing a color space transforming process for the first pixel data to obtain multiple groups of second pixel data of the image in a CIELAB color space, wherein each of the second pixel data includes a luminance component L*, a first color component a* and a second color component b*; adjusting the first color component and the second color component of the second pixel data to obtain multiple groups of third pixel data, and performing a color space transforming process for the third pixel data to obtain multiple groups of fourth pixel data corresponding to the third pixel data in the first color space.