Four people were killed and 10 others were injured in a bomb attack on the governor's temporary headquarters in Aden, the main city in southern Yemen, security officials and medics said.
Governor Nayef al-Bakri was unharmed in the blast at the headquarters of the Aden Faculty of Administrative Sciences, which is housing the governor's offices, the sources said.
It was the first such attack in Aden since pro-government forces retook the city from Iran-backed Shiite rebels in mid-July. The authorities could not immediately identify the perpetrators, the security officials said.
Bakri is known for his close ties to the Islamist Al-Islah Party. He was deputy governor of Aden until the Houthi rebels advanced on the city in March after seizing the capital Sanaa.
Exiled President Abedrabbo Mansour Hadi later appointed him governor, rewarding him for remaining in the city during months of fierce fighting while many other provincial officials fled.
The recapture of Aden by loyalist forces supported by Saudi-led air strikes was a turning point in the conflict, paving the way for their advance across the south, although the rebels still hold Sanaa.