Image Enhancement is a process of improving the quality of an image by improving the contrast of the images. Images acquired underwater usually suffers from non-uniform illumination, low-contrast, motion blur effect due to turbulence in the flow of water, in under ocean environment, scattering of light from different particles of various sizes, diminished intensity and color level due to poor visibility conditions, suspended moving particles and so on. Due to all these factors, various types of noises occur and to reduce the effects arising out of these factors, a number of methods are required to be incorporated to improve the quality of underwater images. The present paper shows a comparative study of the various image enhancement techniques used for enhancing underwater images and introduces a suitable novel hybrid method for improving the image quality.