According to Press TV, the attack, which took place on Thursday near the Syrian city of Manbij, injured five other troops too.
“Two coalition personnel were killed and five were wounded by an improvised explosive device in Syria” at around midnight (21:00 GMT), the coalition said in a statement.
The British Defense Ministry also confirmed that the one of them was from within its ranks.
“The individual was embedded with US forces on a counter-Daesh operation when the incident occurred,” the ministry stated.
The US and its allies have been bombarding what they call Daesh positions inside Syria since September 2014 without any authorization from the Damascus government or a UN mandate.
The strikes, however, have on many occasions resulted in civilian casualties and failed to fulfill their declared aim of countering terrorism.
Since the beginning of the conflict in Syria in early 2011, more than 350,000 people have been killed, according to the United Nations’ estimates.
Syria has, for several times, written to the UN to complain that the US was flagrantly violating its sovereignty. The US supports terrorists fighting to topple President Bashar al-Assad and has repeatedly attacked Syrian army positions.