The people were later removed from the area. It was not immediately clear whether any of the five had entered the embassy building itself, a police spokesperson told news agency TT.
Stockholm and Teheran are involved in a growing diplomatic row over several Swedish citizens held in custody in Iran.
Iran has meanwhile accused a Swedish court of unjustly sentencing a former Iranian official to life in prison over a mass execution of political prisoners in the 1980s.
(Reporting by Anna Ringstrom and Terje Solsvik; editing by Alexandra Hudson)
