Mesh models are among the primary representations for storing 3-D objects, encapsulating detailed geometric information. 3-D mesh watermarking, in particular, plays a central role in the protection of 3-D content. However, frequency-domain methods rely on complex parameterization and spectral decomposition, which are sensitive to mesh topology and resolution and often introduce perceptible artifacts. Spatial-domain techniques, on the other hand, typically embed watermarks in global or randomly selected regions, leading to visible distortions and reduced robustness. To address the above limitations and protect model copyright without compromising the original aesthetic quality, we propose a deterministice PCA-synchronized 3D mesh watermarking method with fullerene-guided carrier selection. First, a deterministic principal component analysis (PCA)–based mesh synchronization algorithm is employed to align the models to a canonical pose. Next, a fullerene-inspired carrier selection strategy is employed to determine the watermark carriers, leveraging the structural characteristics of fullerene molecules to achieve a more rational and effective carrier selection. Finally, to balance the embedding strength and enhance visual quality, the watermark information is embedded using an APQIM (Adaptive Parity-Check Quantization Index Modulation) scheme. The experimental results show that our method can achieve high visual quality with scalable capacity and strong robustness compared with existing methods. The watermarking scheme can resist various attacks, including simplification, smoothing, Gaussian noise, translation, and rotation.