The slain soldier was bid a tearful adieu by his family. Relatives and hundreds of people from neighbouring villages gathered to witness the last rites of the martyr.
Singh, son of a retired railway official, was the eldest of four brothers and the sole bread earner in the family.
He leaves behind his wife Sangeeta Devi, two daughters and a son.
The bodies of four soldiers of 21 Bihar Regiment, killed after "heavily armed terrorists in Pakistani Army uniform" ambushed an Indian army patrol in Jammu and Kashmir Tuesday, arrived in Patna late Wednesday night.
The coffins were immediately taken to their native places in Bhojpur, Saran, and Bihta in Patna districts in special vehicles.
Reports said preparations for the cremation of the other three soldiers from the state are in the final stages in their respective villages.
Five soldiers were killed when the attackers, including men in Pakistani military uniform, barged into Indian territory and ambushed an army patrol at Chakan-da-Bagh sector of the Line of Control (LoC), which divides Kashmir between India and Pakistan.
One soldier was injured.
The other soldiers slain from Bihar were Sambhusaran Rai, who belonged to Ara in Bhojpur district, Vijay Kumar Rai from Bihta in Patna district and Prem Nath and Raghunandan Prasad from Saran district.
Kundalik Mane of the 14 Maratha Light Infantry, hailing from Pimpalgaon Bhudruk in Maharashtra, was also killed in Tuesday's attack.
Bihar Chief Minister Nitish Kumar has announced a state funeral for all the four soldiers of the 21 Bihar Regiment killed in Jammu and Kashmir. He has also announced compensation of Rs.10 lakh each for the families of the slain soldiers.