Recent advances in molecular beam epitaxial growth made it possible to fabricate exotic heterostructures comprised of magnetic films or buried layers (ErAs,GaxMn1-xAs) integrated with conventional semiconductors (GaAs) and to explore quantum transport in these heterostructures. It is particularly interesting to study spin-dependent resonant tunneling in double-barrier resonant tunneling diodes (RTDs) with magnetic elements such as GaAs/AlAs/ErAs/AlAs/GaAs and GaAs/AlAs/GaxMn1-x As/AlAs/GaAs. We present the results of our theoretical studies and computer simulations of transmission coefficients and current-voltage characteristics of RTDs based on these double-barrier structures. In particular, resonant tunneling of holes in the GaxMn1-xAs-based RTDs is considered. Our approach is based on k∙p perturbation theory with exchange splitting effects taken into account. © 2000 American Vacuum Society.