As Ca-3(VO4)(2) is known to be ferroelectric in bulk form at room temperature, we have investigated this material at the nanoscale and at different crystallographic orientations. In this context, self-organized Ca-3(VO4)(2) nanostructures have been grown on top of conducting complex oxide CaVO3 (CVO) thin films deposited by pulsed laser deposition on SrTiO3 (STO) substrates presenting three crystallographic orientations (i.e., (100)STO, (110)STO, and (111)STO). The growth of Ca-3(VO4)(2) nanostructures occurs at high temperature and is related to the oxidation of the CVO phase. Because the nanostructures exhibit epitaxial relationships with the CVO matrix, depending on the substrate orientation, we show that particular morphologies of nanostructures could be obtained with defined shape and orientation. Atomic force microscopy, transmission electron microscopy, and electron diffraction experiments were performed to characterize the different epitaxial relationships, and electron energy loss spectroscopy measurements confirm the oxidation transformation of the vanadium nanostructure (V5+) from the CVO film (V4+). Finally, piezoforce microscopy of the different nanostructures shows a nonzero piezoresponse, with in particular a clear piezoelectric activity for one type of orientation (i.e., [554]Ca-3(VO4)(2)) on (110)STO). In addition to the study of Ca-3(VO4)(2)2 nanostructures, a complete investigation of the different domains of orthorhombic CVO film has been conducted for the three orientations. This oxidation process is particularly innovative and can lead to a way of synthesis of nanocapacitors in a single-step process.