Børge Brende and Mohammad Javad Zarif signed three "export credit" deals aimed at funding "development and infrastructure projects", Iran's foreign ministry said in a statement.
Iran has struggled to tap international finance as many banks fear US penalties if they do business with the Islamic republic.
A landmark deal between Tehran and world powers, which was signed in July last year and came into force in January, saw many international sanctions on Iran lifted in exchange for curbs to its nuclear programme.
European countries have been keen to do business with one of the last frontier markets, but Washington has maintained sanctions related to Iran's human rights record and missile programme.
"After the lifting of sanctions, good opportunities have emerged for cooperation and Norway is ready to utilise the post-deal situation to expand cooperation in various fields," Brende said, according to the official IRNA news agency.
The Norwegian minister met other top officials during his one-day visit, including Supreme National Security Council secretary Ali Shamkhani, before leaving for Pakistan.
An Iranian opposition group warned that the republic would use Brende's visit "for propaganda purposes and to justify its repressive policies at home and its support for international terrorism and Islamic extremism."
"This trip takes place amid a wave of mass executions in Iran. Just today [Wednesday, ed.] the regime carried out five public executions," Shahin Gobadi of the Foreign Affairs Committee of the National Council of Resistance of Iran (NCRI) said in a statement provided to The Local.
"The notion of moderation under [President Hassan] Rouhani is a total myth, and all the factions of the regime are in consensus regarding human rights abuses and export of terrorism," Gobadi added. "The regime’s human rights abuses and its appalling record should be addressed publicly and explicitly during this trip.”