Abstract: To address the constrained development of conventional neutron detectors caused by the supply shortage of helium-3 (³He), this paper proposes a novel V-shaped trench SiC neutron detector. By optimizing the ratio of trench width to cell size and the V-shaped included angle, the detection efficiency of the detector filled with ⁶LiF is improved from 13.13% to 17.47%, representing a relative increase of 33%. When the conversion material is replaced with ¹⁰B, a detection efficiency of 47.87% is achieved while maintaining a relatively large device dimension, significantly alleviating the self-absorption effect inherent to ¹⁰B. Furthermore, the filling ratio of the conversion material is found to exert a significant influence on detector performance; for the ¹⁰B-filled detector, a peak detection efficiency of 52.08% is attained at a filling ratio of 80%. These results demonstrate that the proposed V-shaped trench structure offers notable advantages in both enhancing neutron detection efficiency and mitigating self-absorption, thereby providing a viable technical pathway for replacing ³He-based detectors.