The plaque unveiled today by the Basij paramilitary forces carries a list of condemnations of America uttered by the Islamic republic's late founder, Grand Ayatollah Ruhollah Khomeini.
During the gathering, the students set fire to US, British and Israeli flags.
Iran and the US have had no diplomatic relations since 1979, when Iranian students stormed the embassy and took 52 Americans hostage for 444 days.
Hard-liners in Iran have stepped up displays of anti-American fervor since the signing of a landmark nuclear agreement with Washington and five world powers last month.