Nondestructive magnetic measurements, such as hysteresis measurements and Barkhausen emission, have the potential to serve as effective methods of determining case depth in ferrous materials. The inspection of surface modified ferromagnetic materials is limited by the lack of understanding of the complex dependence of Barkhausen emission on microstructure, which may vary with depth in surface modified materials. Characterization of the depth profiles of magnetic properties provides a greater understanding of the microstructural variations since Barkhausen signals depend on the nature and density of pinning sites for domain walls, particularly in the surface layer. With an aim of understanding the relationship between magnetic properties and microstructure related to case depth of surface-hardened magnetic materials, depth profiles of magnetic properties were completed on surface-hardened 1045 steel samples. Hysteresis loop and Barkhausen effect measurements were made on a series strip samples with various dislocation densities cut from induction hardened rods with case depths ranging from 0.5 mm to 15 mm. The magnetic properties, including coercivity and Barkhausen emission, exhibit correlation with hardness which is closely related to dislocation density. The relationships between the Barkhausen model parameters and the microstructure of surface hardened samples were also examined. Quantitative analysis of the hysteresis and Barkhausen data revealed simple relationships between the model parameters and the domain wall pinning strength, which was determined by simulating the measured hysteresis loops. The pinning coefficient k, which characterizes the average domain wall pinning strength, showed depth dependence similar to coercivity. The model parameters of fluctuation amplitude A, and correlation length [Xi], were found to be inversely proportional to k.