The reaction of [Mo3S4(H2O)(9)](4+) (1) with hydrotris(pyrazolyl) borate (Tp) ligands produced [Mo(3)S(4)Tp(3)]Cl(.)4H(2)O ([3]Cl(.)4H(2)O) in an excellent yield. An X-ray structure analysis of [3]Cl(.)4H(2)O revealed that each molybdenum atom bonded to the Tp ligand. We report four salts of 3, [3]Cl(.)4H(2)O, [3]tof(.)2H(2)O, [3](PF6H2O)-H-., and [3]BF(4)(.)2H(2)O in this paper. The solubility and stability of the chloride salt in organic solvents differ completely from those of the other salts. We have also prepared a new compound, [Mo(3)OS(3)Tp(3)](PF6H2O)-H-. ([4](PF6H2O)-H-.), via the reaction of [Mo3OS3-(H2O)(9)](4+) (2) with KTp in the presence of NH4PF6. All the molybdenum atoms bonded to Tp ligand. H-1 NMR signals corresponding to nine protons bonded to three pyrazole rings in one Tp were observed in a spectrum (at 253 K) of [3]BF(4)(.)2H(2)O. It shows that cluster 3 has a 3-fold rotation axis in CD2Cl2 solution. Twenty-one H-1 NMR signals corresponding to twenty-seven protons bonded to nine pyrazole rings in three Tp ligands were observed in a spectrum (at 233 K) of [4](PF6H2O)-H-.; obviously, 4 has no 3-fold rotation axis, in contrast to 3. The short CH...mu S-3 distance caused large upfield chemical shifts in the H-1 NMR spectra of 3 and 4. The reaction of 3 with metallic iron in CH2Cl2 produced [Mo(3)FeS(4)XTp(3)] (X = Cl (5), Br (6)). X-ray structure analysis of 5 has revealed the existence of a cubane-type core Mo3FeS4. Complex 3 functions as a metal-complex ligand for preparing a novel mixed-metal complex even in nonaqueous solvents. The cyclic voltammogram of 5 shows two reversible one-electron couples (E-1/2 = -1.40 and 0.52 V vs SCE) and two irreversible one-electron oxidation processes (E-pc = 1.54 and 1.66 V vs SCE).