This work characterizes the damage evolution of adhesively bonded scarf joints according to the substrate materials (AU4G-type aluminum alloy and XC18-type steel), the adhesive thickness (ej) and the scarf angle (alpha). Experimental results were obtained by strain gauge measurements. This method allows distinguishing three damage thresholds, which characterize the damage evolution of the adhesively bonded scarf joint. Contrary to most numerical studies, which determine the strength of the bonded joints according to the ultimate failure load, in this study a failure criterion implemented in ABAQUS was used to predict progressive damage evolution of the adhesively bonded scarf joints. The obtained results show the viability of the numerical model to predict the damage evolution of the bonded joint as a function of the studied key parameters. Nevertheless, for high adhesive thickness or a very low scarf angle the comparison also shows the limits of the numerical model.