Ultra-fine grained commercially pure (CP) Ti with an average grain size of 120 nm was fabricated by equal channel angular pressing (ECAP) following cold rolling (CR) and swaging at room temperature. Uniaxial tensile creep tests, transmission electron microscope and scanning electron microscope were applied to investigate the creep behavior and mechanism of ultra-fine grained CP Ti. The results showed that a significant creep deformation at room temperature occurred in the ultra-fine grained CP Ti. The steady creep rate increased from 2.8×10-7 s-1 to 1.5×10-4 s-1 as the creep stress increased from 640 MPa to 760 MPa. Ultra-fine grained CP Ti had lower steady creep rate than the coarse-grained CP Ti at the same stress level, which indicated that ultra-fine grained CP Ti had higher creep resistance. The creep mechanism of ultra-fine grained CP Ti is dislocation movement. The creep fracture morphology of ultra-fine grained CP Ti exhibited ductile fracture with dimples.