Six thorium-based coordination polymers have been hydro/solvothermally synthesized by using trimesic acid (H3btc) as organic linker and their crystal structures have been determined by means of X-ray diffraction technique. Four of them crystallized in N,N-dimethylformamide (DMF) solvent (Th3O(btc)3(OH)(H2O)2·2.9DMF·1.5H2O (1), Th2(btc)2(Hbtc)(DMF)3·dma (2), Th2(btc)3(DMF)2·Hdma (3) & Th(btc)(NO3)(DMF)2·X (X = H2O, DMF (4)). Their occurrence depends on the Th/H3btc molar ratio and the nature of thorium salt source (nitrate for 1, 3, 4, and chloride for 2). Compound 1 exhibits a 3D porous open-framework with honeycomb-like channel (diameter 11 Å) network, delimited by trinuclear oxo-centered thorium units and trimesate ligands. The other solids possess 3D (2, 3) or 2D (4) networks, containing mononuclear thorium ThO9 units. Two other compounds (Th2.25(H2O)(btc)3·2H2O (5) and Th2(OH)2(H2O)2(btc)2 (6)) have been isolated in aqueous medium for different pH ranges. Indeed, in acidic conditions (pH=0.5), compound 5 is formed and composed of isolated mononuclear thorium ThO8 or ThO9 units. At higher pH (5.2), a second phase (6) is observed and its crystal structure is built up from the dinuclear thorium-based units, containing double μ2-OH bridge. When pH reaches 11.2, a mixture of phases 5, 6, and 1 co-exists, and then dense purely inorganic ThO2 is visible for pH = 14. The phases 1, 2, and 5, obtained as pure phases, have been further characterized by thermogravimetric analysis and infrared spectroscopy. Sorption properties have been estimated for the porous compound 1, with nitrogen (77K), CO2, Xe, and Kr at 273K.