In this paper, the stochastic stability and bifurcation characteristics of a multiwalled carbon nanotube (MWCNT)-absorbing hydrogen atoms subjected to the thermal perturbation are studied. A new differential item is introduced to explain the hysteretic phenomena of a MWCNT's stiffness. The constitutive model of a MWCNT is obtained, and its fitting effect on experimental data is proved by the partial least-square regression method. The nonlinear dynamic model of a MWCNT-absorbing hydrogen atoms subjected to thermal perturbation is developed, and the stochastic stability and bifurcation characteristics of the system are analyzed. The system's safe basin and reliability function are obtained, and the probability density of the first-passage time is determined. Theoretical analysis and numerical simulation indicate that the system's stability is effected by the thermal perturbation, and the stochastic Hopf bifurcation will appears, which can reduce the actual hydrogen storage capacity of the MWCNTs; the area of the safe basin is reduced when the thermal perturbation increases, and the system's reliability decreases. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.