Non-local means image decomposition Image decomposition with directional filter banks Construction of 2D simulated dataset by gprMax A novel clutter removal method based on non-local means (NLM) filtering for ground-penetrating radar (GPR) is presented. NLM filter which can be considered as a generalization of bilateral filter diverges from other local averaging filters since it determines the pixel weights by investigating the self-similarities in the image. NLM filter is extended to a multiscale-multidirectional version called multiscale directional non-local means (MDNLM) filter. Then, it is used to decompose the GPR image into approximation and detail subbands to capture the intrinsic geometrical structures of GPR image that contain both target and clutter information. After directional decomposition, the clutter is eliminated by keeping the diagonal information as target component. Finally, the inverse transform of the remaining subbands provides the reconstructed clutter-free GPR image. Figure A: The output images for detail and directional subbands of MDNLM method Purpose: The clutter removal methods in GPR images are as important as the GPR radar itself. Since, the detection rate is reported according to these results. Therefore, improvement in the ROC curves mean increase in the detection rate. The constructeed gprMax simulated data results show that NLM filter based method outperforms other state-of-the-art methods. Theory and Methods: The NLM method is extended as multi-scale form using "a trous wavelet transform" and multi-directional form using "directional filter banks" for GPR clutter removal implementation and the formulation is given in simple and concise way. Results: Both visual results and quantitative results are presented for simulated dataset and discussed in detail. In addition, visual results of the real dataset is provided for further analysis. The obtained results proved the superiority of our proposed method. Conclusion: A new GPR clutter removal method based on a multi-scale and multi-directional extension of NLM fillter is proposed. NLM has better performance to extract details and it is more robust to clutter hence outperform the other state of the art algorithms.