District Magistrate Rajmani Yadav said Darya Yurieva was hospitalized with severe eye injuries in Varanasi, a holy Hindu city on the banks of the Ganges river in Uttar Pradesh state.
He said Yurieva arrived in Varanasi three days earlier and was staying at a guesthouse owned by the grandfather of the man who allegedly attacked her.
Police said she had stayed in the same guesthouse for three months earlier this year.
Yurieva said the man threw the acid at her while she was sleeping on the balcony of her room and then fled, Yadav said.
Varanasi is 315 kilometers (195 miles) southeast of Lucknow, the capital of Uttar Pradesh state.