The phase transition temperatures of CsCoCl3·2H2O crystals are investigated via differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Three endothermic peaks at temperatures of 370 K (=TC1), 390 K (=TC2), and 416 K (=TC3) were observed for phase transitions from CsCoCl3·2H2O to CsCoCl3·1.5H2O, to CsCoCl3·H2O, and then to CsCoCl3·0.5H2O, respectively. In addition, the spin-lattice relaxation time T1ρ in the rotating frame and T1 in the laboratory frame as well as changes in chemical shifts for 1H and 133Cs near TC1 were found to be temperature dependent. Our analyses results indicated that the changes of chemical shifts, T1ρ, and T1 are associated with structural phase transitions near temperature TC1. The changes of chemical shifts, T1ρ, and T1 near TC1 were associated with structural phase transitions, owing to the changes in the symmetry of the structure formed of H2O and Cs+ ions. Consequently, the structural symmetry in CsCoCl3·2H2O crystals based on temperature is discussed by the environments of their H and Cs nuclei.