The first quaternary plutonium metal thiophosphates have been synthesized by the reactive flux method and characterized by single-crystal X-ray diffraction: K3Pu(PS4)(2) (I), KPuP2S7 (11), RbPuP2S7 (111), and CsPuP2S7 (IV). All four compounds crystallize in the monoclinic space group P2(1)/c with Z = 4. Compound I has cell parameters of a = 9.157(l) Angstrom, b = 16.866(2) Angstrom, c = 9.538(1), and beta = 90.610(3)degrees. Compound 11 has cell parameters of a = 9.641 (1) Angstrom, b = 12.255(1) Angstrom, c = 9.015(1) Angstrom, and beta = 90.218(1)degrees. Compound III has cell parameters of a = 9.8011(6) Angstrom, b = 12.3977(7) Angstrom, c = 9.0263(5) Angstrom, and beta = 90.564(1)degrees. Compound IV has cell parameters of a = 10.1034(7) Angstrom, b = 12.5412(g) Angstrom, c = 9.0306(6) Angstrom, and beta = 91.007(1)degrees. Compound I is isostructural to a family of rare-earth metal thiophosphates and comprises bicapped trigonal prismatic PuS8 polyhedra linked in chains through edge-sharing interactions and through thiophosphate tetrahedra. Compounds II-IV crystallize in a known structure type not related to any previously observed actinide thiophosphates and contain the (P2S7)(4-) corner-shared bitetrahedral ligand as a structural building block. A summary of important bond distances and angles for these new plutonium thiophosphate materials is compared to the limited literature on plutonium solid-state compounds. Diffuse reflectance spectra confirm the Pu(111) oxidation state and Raman spectroscopy confirms the tetrahedral PS43- building block in all structures.