The incident took place Friday in Mudhaal village, 435 km from here.
Police said a home guard's daughter had gone missing last month, only to resurface after three days from Unnao.
The family suspected Kiran, daughter of another villager Suraj Singh, to be behind the girl's disappearance.
The incensed kin chased Kiran when she was returning after buying groceries, doused her in kerosene and set her ablaze in the middle of the road, in full public view.
The girl ran and slumped outside her home.
She was taken to a medical facility from where she was referred to the Bijnore district hospital where she died Friday night.
A first information report (FIR) was lodged against five people - Bheem Singh, Pintu, Ajay, Babloo and Kailash.
The girl, in her dying declaration before an additional district magistrate, had named the assailants.
The assailants are on the run.
A few days back, a girl was gang raped and burnt alive in a village in Etawah, the home town of Chief Minister Akhilesh Yadav. She succumbed to her injuries Friday.