SG-15 was an SG team created in 2363.
The teams SG-3, SG-12 and SG-15 were called in by Major General George S. Hammond when SG-1 were negotiating with what seemed to be a hostile human race, called the Aschen.
They helped SG-1 in securing the Stargate off-world while they were attacked by members of a race later known as the Serrakin. A few weeks later, in the incident with Mot on P4S-237, they were at SG-1's side when defeating that Goa'uld.
During the invasion of Langara by Anubis Colonel O'Neill requested SG-15 along with SG-11 to act as "technical advisers."
According to Colonel Samantha Carter, SG-15 was lost after a raid on The Trust safe house, attempting to rescue Vala Mal Doran.