Endoscope images suffer from undesired luminance nonuniformity and loss of contrast because of variation of light resource intensity.The illumination-reflectance model and homomorphic filter are discussed for endoscope image enhancement.A novel homomorphic filter based on wavelet transform is proposed,which adopts fast 2D wavelet transform instead of Fourier transform.The wavelet analysis coefficients are processed by using a nonlinear mapping to attenuate the low spatial frequencies and amplify the high spatial frequencies.The experiments show that the new method can eliminate the non-uniform distribution of luminance of endoscope image effectively.Moreover,the method performs well in enhancing the local contrast of endoscope image,and its performance is better than that of the traditional homomorphic filter.