Three members of a family, including an 8-year-old girl, were found hanging in their house in Alipurduar district on Thursday, police said.
Preliminary investigation revealed that 32-year-old Basudeb Pal strangulated his wife Anima, 25, and daughter Ankita, 8, to death with a gamcha (traditional cotton towel) and then hanged them, a senior police officer said.
Basudeb, stated to be a "habitual drunkard", later committed suicide by hanging at the house in Pakriguri village near the West Bengal-Assam border.
The office said the couple had a quarrel last night.
The bodies have been sent for post-mortem examination.
Basudeb used to work as daily labourer, the police said.
Local people said he used to work as a carpenter in Shillong and returned home only Wednesday.
Get Breaking news, live coverage, and Latest News from India and around the world on NDTV.com. Catch all the Live TV action on NDTV 24x7 and NDTV India. Like us on Facebook or follow us on Twitter and Instagram for latest news and live news updates.