District and Sessions Judge Raghuvar Dayal sentenced Laxman Baitha, father-in-law of Priyanka Devi, who was set on fire at Tandpatra village under Padwa police station of Palamau district in September, 2010.
Her husband Jagannath Baitha and another person were acquitted due to lack of evidence.
An FIR had been registered against nine persons by the victim's brother, a resident of Mohammadgunj of the district.
Priyanka, who was married off to Jagannath two years before the incident, was subjected to frequent torture for more dowry of Rs 70,000 and she was burnt to death for failing to meet the demand, he said in the FIR.