First-principle density functional calculations and photoelectron spectroscopy experiments show that triniobium carbide Clusters exist in multiple motifs. The Nb3Cn- (n = 5-10) series have isomers surrounding a triangular Nb-3 base while incorporating Nb-C bonding. We provide evidence of not only C-2 carbon chains but also stable isomers with previously unidentified C-3 and C-4 carbon chains in triniobium carbide clusters.