This study uses a thermal uncoupled thermal-hydraulic-mechanical (THM) model to investigate the interactive behavior of change in pore water pressure, displacement, and temperature of a buffer material in the near-field of the nuclear waste repository. The variation of pore water pressure is contributed to both the deformations of porous space and the swelling of pore water. The deformations are controlled by the thermal expansion coefficients of solid and fluid. Stochastic analysis is performed by using Monte Carlo simulations. The variances of displacement and change in pore water pressure vary spatial-temporally. The variances expresses the variation of displacement and change in pore water pressure in the domain and provides the uncertainty information. The proposed stochastic THM analysis provides a tool for the uncertainty assessment of the nuclear waste repository.