Mature cement pastes are subjected to isothermal, three-minute creep test under uniaxial compression at 20°C, 30°C, and 45°C. The macroscopic experiments are evaluated in the framework of linear viscoelasticity, based on a power-law creep function, considering that spontaneous elastic and time-dependent creep deformations are developing during the short loading phase. The modulus of elasticity is found to decrease slightly, and the creep modulus to decrease significantly with increasing temperature. These macroscopic findings are downscaled, in the field of continuum micromechanics, to microscopic hydrate-gel needles, based on a multiscale model. This allows for quantification of the activation energy of creep of the hydrate-gel, which is close to the activation energy of water.