Targeting at the halo or gradient reversal artifacts appearing on salient edges in the layered tone mapping algorithm of high dynamic range images, an improved layered tone mapping algorithm was proposed. In this algorithm, firstly the abnormal signal characteristics causing halo and gradient reversal artifacts were determined by analyzing the base layer image and detailed layer image obtained via image decomposition. Then the artifacts were recognized and corrected from the gradient of detailed layer image according to the abnormal signal characteristics, and the regularization equation was subsequently established for the corresponding image based on the corrected gradient. At last, conjugate gradient method was adopted to solve the regularization equation. The abnormal signals in detailed layer image were inhibited, and halo or gradient reversal was removed from the resulting mapping image. The proposed algorithm could not only effectively inhibit halo and gradient reversal artifacts in the original layered tone mapping algorithm, but also preserve the detail reproduction capacity as the original algorithm did.