Mustapha al-Shamali was appointed oil minister in Kuwait's new Cabinet, state news agency KUNA said on Sunday after a parliamentary election in the major crude producer last month.
The position was previously held on an acting basis by al-Shamali, after his predecessor, Hani Hussein, resigned in May under pressure from parliament.
Oil policy in the OPEC member state is set by a Supreme Oil Council, so ministerial changes are less important than in other countries.
The new cabinet was sworn in on Sunday before the emir, Sheikh Sabah al-Ahmad al-Jaber al-Sabah, KUNA reported. It includes six members in the royal family and one member of the parliament.
Previous governments included on average four members of ruling al-Sabah family and up to six members of parliament.
The Finance Ministry, which Shamali previously led, will now be headed by Sheikh Salem Abdulaziz al-Sabah, who served for more than 20 years as central bank governor until his resignation in February 2012.
Mohamed Khaled al-Hamad al-Sabah will serve as interior minister, a decree by Kuwait's emir said.
The July 27 parliamentary election brought in an assembly seen as more amenable to the government than some of its predecessors, raising hopes that economic development projects will move forward in the Gulf Arab state.
Kuwait's ruler reappointed Sheikh Jaber al-Mubarak al-Sabah as prime minister after the election and asked him to form a new Cabinet.
The ruling family traditionally holds top posts in the government.
Kuwait has the most open political system in the Gulf Arab region, but parliaments have been repeatedly dissolved over procedural disputes or for challenging the government.