A roadside bomb killed two Sunday morning, while another service member died in a separate attack on Saturday. It provided no further details on the incidents or the nationalities of the troops.
The latest deaths take the total toll among the US-led coalition so far this year to 250, according to an AFP count based on the website icasualties.org.
Roadside bombs, a favourite weapon of Taliban insurgents, have taken a particularly heavy toll in Afghanistan this month.
Six American soldiers died in a huge blast on July 8 in the same eastern region of the country, which is the focus of a NATO push against insurgents along the border with Pakistan.
NATO also said that it killed a number of insurgents with an airstrike in the Mohammad Agha district of eastern Logar province. It did not provide further details.
Fighting in eastern Afghanistan has been raging since spring as NATO tries to clear the area of insurgents.