A novel chemical oxidative polymerization approach has been proposed for the controllable preparation of organic–inorganic hybrid MoOx/polyaniline (PANI) nanocomposites based on the nanowire precursor of Mo3O10(C6H8N)2⋅2 H2O with sub-nanometer periodic structures. The nanotubes, nanowires, and rambutan-like nanoparticles of MoOx/PANI were successfully obtained through simply modulating the pH values to 2.5–3.5, ≈2.0 and ≈1.0, respectively. Through systematic physicochemical characterization, such as scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and so forth, the composition and structure of MoOx/PANI hybrid nanocomposites are well confirmed. It is found that the nanowire morphology of the precursor is the key to achieve the one-dimensional (1D) structures of final products. A new polymerization–dissolution mechanism is proposed to explain the formation of such products with different morphologies, in which the match between polymerization and dissolution processes of the precursor plays the important role. This approach will find a new way to controllably prepare various organic–inorganic hybrid 1D nanomaterials especially for polymer–hybrid nanostructures.