Before plans to introduce the F-4 series failed as a result of improving Sino (Mainland China)-US relations, the Nationalist government signed contracts with Northrop to assemble the F-5E/F on Taiwan Island in 1973 to replace the ageing F-86F/F-100 fleet under Project Peace Tiger (虎安計劃). Six batches of these aircraft were assembled domestically by AIDC, but plans to upgrade them were cancelled in the early 2000s. They became a cornerstone of the ROCAF until the 2020s. Two fatal incidents then accelerated their decommissioning from the remaining fighter wing of the ROCAF, their performance being deemed hopeless against the now-modernized PLAAF; the remaining RF-5Es are to be replaced by the new T-BE-5A Brave Eagle AJT by the mid-2020s.

Introduced in Update "Danger Zone" alongside its American counterpart, the F-5E in ROCAF service has the same capabilities as the original US-built ones, with hard-hitting AAMs/AGMs as well as a variety of loadouts from rocket pods up to 2,000 lb bombs. Although it is not as dominant in air combat as the PLAAF J-7E, the F-5E's ability to carry four AGM-65 Maverick missiles makes it a uniquely valuable aircraft in the Chinese tech tree for precision standoff CAS.