The Western military alliance says on Friday that the soldier was killed in a militant attack, without giving further details.
NATO did not provide the nationality of the soldier and the exact location of the incident.
The death brings to at least 341 the number of NATO troopers have been killed in Afghanistan so far this year.
Foreign troop casualties in Afghanistan have risen steadily since the US invaded Afghanistan in 2001.
According to official figures, more than 2,307 US-led soldiers have been killed in Afghanistan so far.
The security situation remains fragile in Afghanistan despite the presence of 150,000 US-led foreign forces in the country.
Four US soldiers were also killed on Thursday in the war-ravaged country.