Mogherini met with Iranian Foreign Minister Mohammad Javad Zarif ahead of an inauguration ceremony for President Hassan Rouhani in Tehran.
Iran's missile tests and a satellite launch on July 27 were "not in contradiction" with UN resolutions, Zarif's office said in a statement after the meeting.
Britain, France and Germany last week joined the United States in calling for UN action in response to the satellite launch, saying the technology could be used for ballistic missiles and was "threatening and provocative".
"This is the wrong path," Zarif said in the statement.
UN Resolution 2231 was implemented alongside a 2015 nuclear deal between Tehran and world powers, urging Iran to refrain from testing missiles designed to carry nuclear warheads.
Iran denies it is seeking a nuclear weapon and says the missile tests are part of its legitimate defence programme.