The 21-year-old Indian man was reportedly attacked in the wee hours of Saturday, Oct 9 on Edinburgh's Waverly Bridge.
He was punched by one of the men before the second struck him on the head, knocking him to the ground, BBC reported.
On seeing this, three other men joined the attackers in beating up the Indian. The victim was then left on the ground as all the five men and the women fled from the scene.
The Lothian police have termed the "appalling assault" a racially-motivated attack, in which the victim sustained a broken jaw.
"This has been an appalling assault levied against the victim for no reason other than his race and his efforts to come to a young woman's assistance," a police spokesperson is quoted as saying.