Terahertz　digital　holography　is　an　attractive　combination　of　terahertz　imaging　and　digital　holography,　which　possesses　the　unique　propagation　and　penetration　ability　of　terahertz　radiation　as　well　as　the　advantages　of　high　spatial　resolution　full-field　phase-contrast　imaging.　We　proposed　a　continuous-wave　off-axis　reflective　terahertz　digital　holography　to　measure　the　morphology　of　the　object.　An　experimental　setup　was　built　using　a　2.52　THz　(118.83　mu　m)　far-infrared　gas　laser　295-FIR　and　a　pyroelectric　array　detector.　The　field　of　view　was　expanded　by　stitching　the　reconstructed　amplitude　and　phase　distributions　of　three　consecutive　holograms　after　sub-pixel　registration.