An image capturing device with automatic white balance and an automatic white balance correction method are provided. The image capturing device includes a lens assembly, a light diffuser, an image sensor and a processor. The relative position of the light diffuser and the lens assembly is fixed. The processor is electrically connected to the image sensor having a first sensing region and a second sensing region. The light diffuser converts a fraction of the incident light to the reference light. The first sensing region converts the incident light to the display image information. The second sensing region converts the reference light to the correction information. The processor determines a reference gain average according to at least one color gain of the correction information and obtains at least one color gain correction value according to the reference gain average to adjust the white balance setting of the display image information.