The attacks in Wardak province's Sayedabad district targeted the Governor's office and a NATO outpost. The first attack was carried out by a militant on foot followed by a truck bomb blast that destroyed a local market.
"A suicide bomber on foot detonated near the gate of the base in Saidabad, Wardak province, opening the way for a truck suicide bombing that followed him," provincial spokesman Shahiddullah Shahid told the AFP news agency.
At least 47 people were injured in the attacks and ten civilians with grievous injuries have been evacuated to Kabul, AFP report said.
No NATO staff was killed in the attacks, BBC reported quoting NATO officials.
"The number of wounded is so high that it can hardly be counted. Lots of people have been wounded and much of the Sayedabad bazaar has been destroyed," Wardak police spokesman Abdul Wali told AFP.
Militants had attacked the same NATO outpost last year, killing five Afghans and injuring several American soldiers.