In this paper an in-situ self-damage sensing of a bi-directional carbon fiber reinforced polymer (CFRP) composites using electrical resistance measurement is presented. Three configurations of Four probes: surface, through-thickness, and oblique probes was used for data collection while the composite is subjected in quasi-static three points bending loading. Upon loading, composite realtime monitored electrical resistance increased continuously until complete failure for all electrodes configurations. Oblique electrodes configuration proved to be more suitable and sensitive for damage investigation due to good agreement between measured load-deflection and simulated results obtained from a developed COMSOL Multiphysics Numerical model. On this consideration, three mains stages have been retained for the composite damage process characterization: No significant damages stage due to fibers elasticity behavior, minor damages stage where partial fiber breakage, inter-ply delamination and fiber buckling occurs and finally the major damages stage denoted by an abrupt electrical resistance due to the composite sudden and complete failure.