Cobalt Ferrite/Barium Titanate nanotube arrays were obtained in anodic aluminum oxide templates (AAO) of 100 nm pore diameter by a two step sol-gel process. Each phase was grown in several wetting – drying cycles starting from the cobalt ferrite layers with the barium titanate on top. As-dried composite structures were sintered at 700 C. The composite nanotubes showed a fine polycrystalline microstructure with an average grain size of 5 nm. The formation of both spinel and perovskite structures was verified by High Resolution Transmission Electron Microscopy (HR-TEM) on isolated nanotubes. The growing rate by layer was found to be lower for the BaTiO3 on top of CoFe2O4 than the later on top of the AAO. Wall sizes were estimated by Z-contrast as 9.8 nm for one layer of CoFe2O4 and 6.6 nm for six layers of BaTiO3. Magnetic properties were studied by VSM. Samples showed ferromagnetic behavior with low coercive values. By means of a finite element model the deformation and stress on the piezoelectric phase was estimated and used to simulate the magnetization reversal under stress in the composite nanotubes, using an updated micromagnetic framework to include the magnetostriction effect. Simulation results showed that a curling mode is expected with opposite vortex states at the end of the nanotubes. The change in the vortex domain structure under voltage driven applied stress is presented and discussed.