The incident took place yesterday when the victim was travelling to Rewari in Ajmer-Haridwar train, after a tour of Uttarakhand with her friends, Dy SP Ranjna Tyagi said.
The unidentified youth eve-teased and also tried to loot the woman, police said, adding that when she resisted the harassment, she was thrown out of the train by him.
The injured girl was later rushed to the hospital in a serious condition, the GRP said.
An inquiry has been initiated into the incident and the GRP are on a lookout for the absconding accused.
Railway police have registered a case against the accused.