Iranian Vice-President for Executive Affairs Mohammad Shariatmadari conveyed the invitation in a meeting on Thursday with Buhari in the Nigerian capital city of Abuja.
Buhari has been invited to attend the 3rd Gas Exporting Countries Forum (GECF) Summit due to be held in Tehran in late November.
Shariatmadari in the meeting also underscored the necessity for increased international cooperation between Tehran and Abuja in all fields, energy in particular.
Buhari, for his part, congratulated the Iranian nation and government on the successful conclusion of Iran nuclear talks, saying, "This important global event would have a significant effect on the relations of all countries (with Iran)."
He also appreciated the invitation and emphasized that he would travel to Iran and attend the Summit.
The Gas Exporting Countries Forum (GECF) is a gathering of the world's leading gas producers and was set up as an intergovernmental organization with the objective to increase the level of coordination and strengthen the collaboration among member countries.
The member countries of the forum are: Algeria, Bolivia, Egypt, Equatorial Guinea, Iran, Libya, Nigeria, Qatar, Russia, Trinidad and Tobago, United Arab Emirates and Venezuela. Iraq, Kazakhstan, the Netherlands, Norway, Oman and Peru have the status of observer members.