Officials said the vehicle was traveling at a high rate of speed down Florence Avenue when it hit the tree near Halldale Avenue shortly before 3 a.m.
The force of the crash took down the tree and ejected five of the women from the SUV. The sixth had to be extricated from the vehicle.
The women's identities have not been released, but all of them were between 20 and 30 years old.
The cause of the crash remains under investigation. Anyone with information about the crash was asked to call police (323) 421-2577.