National Iranian Oil Co. (N.I.O.C)
National Iranian South Oil Co. (N.I.S.O.C)
Iranian Offshore Oil Co.
Iran Central Oil Fields Co.
Petroleum Engineering & Development Co.
Pars Oil and Gas Co. (P.O.G.C)
Pars Special Economic Energy Zone Co.
Iran Oil Terminal Co.
National Iranian Drilling Co.
Exploration Services Co.
Petro Iran Co.
Iranian Fuel Conservation Organization (I.F.C.O.)
Manufacturing Support and Procurement Kala Naft Tehran Co.
Gachsaran Oil and Gas Production Co.
Tehran Oil Refinery Co.
Tabriz Oil Refinery Co.
National Iranian Petrochemical Co. (N.I.P.C)
Iranian Petrochemical Companies
Iranian Petrochemical Developments Plants
Iranian Petrochemical New Plants
Kala Petrochemical Co.
Imam Khomeini Petrochemical Co.
National Iranian Oil Products Distribution Co. (N.I.O.P.D.C.)
Iranian Oil Refineries
National Iranian Oil Engineering & Construction Co.
Pipeline and Communication Co.
Iranian Power Ministry
Iranian Power Generations
National Iranian Gas Co. (N.I.G.C.)
Iranian Gas Refineries Co.
Regional (state) Gas Companies
South Pars Gas Companies
South Parts Gas Co. (S.P.G.C.)
South Pars Gas Field Development Project (Phases 1, 4, 5, 6, 7, 8, 9, 10, 17, 18)
Tehran Province Gas Co.
Ardebil Province Gas Co.
Oil Industries Engineering & Construction Co. (OIEC)
Petrochemical Industries Design and Engineering Co. (P.I.D.E.C.)
Chagalesh Consulting Engineers Co.
Sazesh Consulting Engineers Co.
Namvaran Consulting engineers Co.
Tarh-O-Palayesh Engineering Co.
Iran International Engineering Co.
Behran Oil Co.
Pars Oil Co.
Iranian Power Plant Projects Management Co. (MAPNA)
National Iranian Copper Industries Co.
Imam Khomeini International Airport (I.K.I.A.) Project