Micro/nano-structured Bi2Te3 bulk materials were prepared by cryogenic grinding followed by spark plasma sintering. The densification behavior, microstructure development, and thermal conductivity properties of as-prepared Bi2Te3 samples were investigated. It was found that rapid densification with maximum compressive strain rate of 2.2x10(-3) s(-1) at 310 degrees C were observed under a uniaxial pressure of 60 MPa. The as-prepared samples exhibit ultra thermal conductivity, which are attributed to strong phonon scattering by nano-grain boundaries.