Dionisio Vilca set off on his search, protesting that the authorities had abandoned efforts to find his police officer son Cesar.
Cesar Vilca had been missing for 20 days, after his unit came under attack by rebels in the southern Cusco region.
Another officer, Luis Astuquillca, was shot in the leg but walked for 17 days through the rainforest to safety.
With the help of two local people who had spotted Cesar's body, Mr Vilca set off to recover his remains.
Travelling in a pick-up truck, the group reached the spot and took the police officer's corpse back to the nearest community.
Mr Vilca had complained that the authorities had wound down their efforts to locate Cesar.
But the interior ministry noted that there had been "an intense and prolonged search"  that had cost the lives of three members of the security forces.
Cesar Vilca and his unit were deployed on 12 April to search for a group of 36 gas workers abducted by Shining Path rebels.
They came under fire from the guerrillas and four officers were killed.
The hostages were released by their captors six days after being abducted in a remote region close to the Ene-Apurimac valley - one of the last strongholds of the Shining Path.
The Shining Path posed a major challenge to the Peruvian state in the 1980s and early 1990s, but is now reduced to small gangs involved in cocaine trafficking.
A Peruvian father has recovered the body of his son, after embarking on a nine-hour journey through the jungle.