In this paper a subspace based technique is proposed for removal of additive white noise in images. The method is based on Time-Domain constrained (TDC) estimator in which the residual noise energy is kept below a threshold while minimizing the signal distortion. The denoising technique employed prewhitening method prior to the subspace filter which is proven to give remarkable results. Experiments were carried out on noise-free images corrupted with simulated additive white noise. The results indicate that the proposed methods provide performance better than Wiener filter in terms of the root mean square error and structural similarity index measure. © 2011 IEEE.