The Saturday blast near university in Kayseri that targeted a public bus also wounded 55 other soldiers and civilians, the Guardian reported.
In a statement, Erdogan said the “separatist terrorist organisation” the PKK was responsible for Saturday’s attack, linking it to developments in Iraq and Syria.
He said that Turkey was under “joint attack” by terrorist organisations.
After Erdogan’s comments, nationalist protesters on Saturday ransacked the local headquarters of the pro-Kurdish Peoples’ Democratic party (HDP) in Kayseri and several other cities.
The bomb had exploded at the entrance gate to Erciyes University and hit the bus that was carrying soldiers on leave and other passengers.
The explosion came a week after a similar attack had killed more than 30 police officers.
Television pictures showed the smouldering wreckage of the bus, as the wounded were taken to waiting ambulances.
Turkey faces multiple security threats, including spillover from the fight against the IS in northern Syria, where it is a member of the US-led coalition against the militant group.
It also faces regular attacks from Kurdish militants who were waging a three-decade insurgency for autonomy in largely Kurdish south-east Turkey.