Terahertz　(THz)　waves　have　many　important　characteristics,　e.g.,　fingerprint　spectrum,　low　energy　and　penetrability,　thus　show　great　potential　and　wide　application　value　in　many　fields　such　as　biomedical　imaging,　industrial　non-destructive　testing,　cultural　relics　protection,　security　inspection　and　anti-terrorism.　With　the　development　of　THz　sources　and　detectors,　the　progress　of　THz　imaging　is　also　constantly　advancing.　THz　confocal　imaging　realizes　high　axial　resolution　by　removing　stray　light　of　the　non-focus　planes　by　point　illumination　and　small　aperture　diaphragm.　This　imaging　approach　obtains　object　depth　information　layer-by-layer.　In　this　paper,　we　illustrated　a　THz　confocal　scanning　imaging　system　which　three　types　of　lenses　are　designed　and　used　to　verify　its　focal　capability　for　imaging　illumination,　i.e.,　THz　super-oscillating　lens　(TSOL),　Fibonacci　lens　(FBL)　and　transmissive　convex　lenses　(TCL).　TSOL　can　produce　long　focal　depth　and　subwavelength　focused　beam.　FBL　is　a　diffractive　lens　that　produces　multiple　foci　along　the　axial　coordinate.　TCL　produces　one　focal　point　in　far-field,　which　is　the　typical　THz　lens　applied　in　various　THz　imaging　systems.　The　implementation　and　calibration　of　three　types　of　THz　confocal　imaging　systems　are　introduced　in　detail,　thereafter　the　corresponding　results　are　shown　and　compared.