In the field of radar signal processing, anti-jamming is an important research branch. Interrupted sampling repeater jamming (ISRJ) is an important type of active deception jamming, which poses a serious threat to radar detection and identification. In order to combat ISRJ, this chapter proposes a jamming suppression method based on linear canonical domain by combining time-frequency (TF) analysis with line segment detection. Firstly, the distribution characteristics of the signal in the short-time linear canonical transform (STLCT) domain are derived. The flexibility of the three free parameters of linear canonical transform significantly improves the TF resolution, and a fast STLCT algorithm is proposed to construct the TF image of the radar echo. Then, the TF image is subjected to canny edge detection and dilation operations, and the position of the discontinuous line segment (representing jamming signals) is detected by Hough transform and filtered. Finally, the inverse STLCT is used to obtain the suppressed output result. Simulation experiments verify the effectiveness of the new method.