According to the Agreement between the Government of Vietnam and the Government of Iran on the mutual abolition of visas for holders of official or service passports, signed on October 6, 2016, effective from July 21, 2017:
(1) Citizens of both Parties, holding valid official or service passports, shall be exempted from visa requirements for the entry into, exit from and transit through the territory of the other Party for the maximum period of ninety (90) days.
Either Party may extend, in accordance with its laws and regulations, the duration of stay for the persons referred to paragraph (1) of this Article upon requests in writing of the Diplomatic Mission or Consular Posts of the other Party whose citizens the passport holders are.
(2) Citizens of both Parties, holding valid official or service passports, assigned to permanent Diplomatic, Consular Mission or international organization offices located in the territory of the other Party, including their family members holding valid official or service passports shall be exempted from visa requirements for the entry into, exit from and stay in the territory of the other Party during their assignments, provided that their assignment is notified to the other Party officially thirty (30) days before their arrival in the receiving Party.
Citizens of both Parties holding valid official or service passport entering the other Party’s territory for the purpose of journalism shall be subject to receive appropriate visa before their entry into the other Party’s territory.
Excluding the citizens mentioned in the paragraph (2) of this Article, citizens of both Party, holding valid official or service passport entering the other Party’s territory for the purpose of remunerated activities, for which a work, permit is required under the national legislation of the receiving Party, shall be subject to apply for appropriate visa before their entry into the other Party’s territory.
The original official agreement between Vietnam – Iran is as follows:
Agreement between Vietnam and France regarding visa exemption for short stays on a reciprocal basis for diplomatic passport holders. Signed on October 6, 2004, and effective from July 1, 2005.