Terahertz　(THz)　radiation　is　able　to　penetrate　many　different　types　of　nonpolar　and　nonmetallic　materials　without　the　damaging　effects　of　x-rays.　THz　technology　can　be　combined　with　computed　tomography　(CT)　to　form　THz　CT,　which　is　an　effective　imaging　method　that　is　used　to　visualize　the　internal　structure　of　a　three-dimensional　sample　as　cross-sectional　images.　Here,　we　reported　an　application　of　THz　as　the　radiation　source　in　CT　imaging　by　replacing　the　x-rays.　In　this　method,　the　sample　cross　section　is　scanned　in　all　translation　and　rotation　directions.　Then,　the　projection　data　are　reconstructed　using　a　tomographic　reconstruction　algorithm.　Two-dimensional　(2-D)　cross-sectional　images　of　the　chicken　ulna　were　obtained　through　the　continuous-wave　(CW)　THz　CT　system.　Given　by　the　difference　of　the　THz　absorption　of　different　substances,　the　compact　bone　and　spongy　bone　inside　the　chicken　ulna　are　structurally　distinguishable　in　the　2-D　cross-sectional　images.　Using　the　filtered　back　projection　algorithm,　we　reconstructed　the　projection　data　of　the　chicken　ulna　at　different　projection　angle　intervals　and　found　that　the　artifacts　and　noise　in　the　images　are　strikingly　increased　when　the　projection　angle　intervals　become　larger,　reflected　by　the　blurred　boundary　of　the　compact　bone.　The　quality　and　fidelity　of　the　2-D　cross-sectional　images　could　be　substantially　improved　by　reducing　the　projection　angle　intervals.　Our　experimental　data　demonstrated　a　feasible　application　of　the　CW　THz　CT　system　in　biological　imaging.　(C)　2018　Society　of　Photo-Optical　Instrumentation　Engineers　(SPIE)