Majorana zero modes (MZMs), which serve as a key platform for realizing fault-tolerant topological quantum computing, remain challenging in excitation and regulation. In this work, we propose chiral nanoribbon-superconductor hybrids as a platform for realizing multiple MZMs. The hybrid system comprises several intertwined helical chains placed on an $s$-wave superconductor, where a geometric spin-orbit coupling (SOC) varying spatially across helical chains, replaces the traditional Rashba SOC. Using tight-binding models and the Green's function technique, we compute the topological phase diagrams and zero-bias tunneling conductance in the hybrid systems. Numerical results reveal a fragmentation phenomenon occurring in the topological phase as the number of chains increases, and a discrepancy between the topological invariant and the quantized conductance in some specific cases. Furthermore, some overlapping regions of two adjacent topological diagrams exhibit trivial invariants while displaying an increased quantized zero-bias conductance. In addition, Majorana polarization appears and is determined by the chirality of the nanoribbons, and is closely associated with the chirality-induced spin polarization. These findings establish chiral nanoribbon-superstructure hybrids as tunable multichannel systems for regulating multiple MZMs and Majorana polarization.

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• Chirality
• Majorana bound states
• Nanoribbon