Since Arabic writing has a robust baseline, several state-of-the-art recognition systems for handwritten Arabic produce use of baseline-dependent characteristics. For modern Arabic documents, the baseline can be detected reliably by obtaining the maximum in the horizontal projection profile or the Hough transformed image. However, the performance of these techniques leaks significantly on Historical Arabic Documents. In this paper, we introduce an effective novel approach to baseline detection in Historical Arabic Documents which is based on Based on Voronoi Diagrams. The proposed technique is carried out, verified and validated on a dataset of Warped Historical Arabic Documents based on affecting by warping percentage.