Abstract: With the development of communication technology, the terahertz frequency band has become a hot spot in 6 G communication. This paper designs two terahertz filters with quasi-elliptical response based on the passband of 212 GHz~218 GHz using metal waveguides. The designed filters utilize TE₂₀₁ resonant cavities to introduce transmission zeros (TZs) and improve the rectangular coefficient of the filter. By controlling the position and size of the coupling structure between resonators, the coupling relationship can be adjusted, and then the TZ position can be adjusted to achieve bandpass filters with different out-of-band suppression, which has good design flexibility and low cost. The simulation design results show that filter 1 has a passband of 211.91 GHz~218.17 GHz, an in-band insertion loss of less than 1.38 dB, and two TZs at 209.80 GHz and 220.54 GHz; filter 2 has a passband of 211.78 GHz~218.36 GHz, an in-band insertion loss of less than 1.21 dB, and two TZs at 220.41 GHz and 221.82 GHz, both of which have good electrical performance.