This　paper　presents　an　ultra-wideband　detector　linear　array　for　4THz　band.　The　FET-based　detectors　coupled　with　antenna　are　strictly　designed　in　65nm　CMOS　technology.　The　current　response　is　analyzed　with　non-quasi　state　and　nonlinear　transistor　model.　Simulated　return　loss　demonstrate　the　-3dB　bandwidth　of　the　antenna　is　from　3.6　to　5THz.　The　CMOS　integrated　linear　array　demonstrates　a　promising　application　in　high-resolution　terahertz　spectrometer　and　imaging　fields.