Hierarchical decryption of 3D objects supports multi-level visual access control and is widely used in digital rights protection and secure data transmission. However, existing methods often encrypt adjacent mantissa bits continuously, causing cumulative bit-level perturbations that lead to geometric distortion and reduced visual fidelity in decrypted objects. To mitigate this, we propose a non-contiguous 3D object encryption method with multi-level visual access control that balance security and visual quality. Using an IEEE 754-based mantissa segmentation approach, we insert fixed-length gap bits between access levels to break perturbation continuity and reduce geometric noise. By assigning non-overlapping bit segments to each access level, the method enables multi-level decryption with clear level separation and reliable visual reconstruction. Experiments show that our method achieves lower root mean squared error(RMSE) and Hausdorff Distance(HD) than conventional schemes while preserving clearer visual distinction between access levels. This ensures better object quality even at lower access levels. In terms of security, our method increases the key space and ciphertext randomness, improving resistance to brute-force and statistical attacks.