The paper compares numerically modeled crack propagation in a steel specimen with a real process of fiber separation. The objective of the study was to perform numerical analysis of crack propagation in order to determine the shape of a crack and the distribution of stresses in the entire model. A CAD model of the test specimen was prepared based on geometric parameters determined for a real model. The numerical analysis was performed using the computer simulation program Abaqus 6.14. The experiment of specimen bending was conducted using bench tools. Crack propagation was simulated by the numerical method xFEM which enabled visualization of fiber separation in the test specimen. The numerical results of crack propagation were compared with the experimental findings about cracking in a real specimen.