Interior Minister spokesman Sediq Sediqqi said that eight others were wounded in the attack, and that police were working to identify the nationalities of the victims.
“The suicide bomber targeted a minibus of security guards of a foreign company, right now we are working to identify the nationalities of the victims,” said Sediqqi.
But a police official told The Associated Press that the 14 dead were Nepalese citizens working as security guards for the private company that was attacked.
The official, who did not want to give his name as he was not authorised to speak to the media, said the wounded included four Afghan civilians.
Dozens of police and many ambulances rushed to the scene to take the victims to hospitals.
Taliban spokesman Zabihullah Mujahid claimed responsibility for the attack.
It is the first attack in Kabul since the start of holy fasting month of Ramadan on June 6. The last attack in the Afghan capital on April 19 left 64 dead and more than 340 wounded.
That attack was claimed by the Taliban, who have been waging an insurgency against the Western-backed Kabul government since they were ousted from power by a US-led invasion in late 2001.
Washington recently announced an expansion of the US military’s authority to conduct air strikes against the Taliban, significantly boosting Afghan forces who have limited close air-support capacities.
US forces have been in an advisory role in Afghanistan since the start of 2015 and were only authorised to hit Taliban targets for defensive reasons, or to protect Afghan troops.
The changes mean US troops can now work more closely with local fighters in striking the Taliban, who have demanded the departure of all foreign forces.