The electronic structures, chemical bonds and stabilities of \rmTa_4\rmC_n^-/0 (n = 0–4) clusters are investigated by combining anion photoelectron spectroscopy with theoretical calculations. The vertical detachment energy values of \rmTa_4\rmC_n^- (n = 0–4) anions are measured to be (1.16 ± 0.08), (1.35 ± 0.08), (1.51 ± 0.08), (1.30 ± 0.08), and (1.86 ± 0.08) eV, and the electron affinities of neutral Ta₄C_n (n = 0–4) are estimated to be (1.10 ± 0.08), (1.31 ± 0.08), (1.44 ± 0.08), (1.21 ± 0.08), and (1.80 ± 0.08) eV, respectively. It is found that the geometry structure of \rmTa_4^- cluster is a tetrahedron, and the most stable structure of \rmTa_4\rmC_1^- has a carbon atom capping one face of the \rmTa_4^- tetrahedron, while in the ground state structure of \rmTa_4\rmC_2^- cluster, two carbon atoms cap two faces of the\rmTa_4^- tetrahedron, respectively. The lowest-lying isomer of \rmTa_4\rmC_3^- cluster holds a cube-cutting-angle structure. The ground state structure of \rmTa_4\rmC_4^- is a 2 × 2 × 2 cube. The neutral Ta₄C_n (n = 0–4) clusters have similar structures to their anionic counterparts and the neutral Ta₄C₄ cluster can be considered as the smallest cell for α-TaC face-centered cube crystal. The analyses of molecular orbitals reveal that the SOMO of \rmTa_4\rmC_3^- is mainly localized on one tantalum atom, inducing a low VDE. Our results show that the Ta-Ta metal bonds are replaced by Ta-C covalent bonds gradually as the number of carbon atoms increases in \rmTa_4\rmC_n^-/0 (n = 0–4) clusters. The per-atom binding energy values of \rmTa_4\rmC_n^-/0 (n = 0–4) clusters are higher than those of \rmTa_4+n^-/0 (n = 0–4) clusters, indicating that the formation of Ta-C covalent bonds may raise the melting point. The per-atom binding energy of neutral Ta₄C₄ is about 7.13 eV, which is quite high, which may contribute to the high melting point of α-TaC as an ultra-high temperature ceramic material.