HARARE, Zimbabwe (AP) _ A guerrilla fighter spent the past eight years in a mountain cave unaware that Zimbabwe's war for independence ended in 1980, the country's largest newspaper reported today.

The Herald said the guerrilla took refuge in a cave in the eastern highlands in 1978 and spoke to no one until hunters found him last November. The newspaper said he left the cave only to seek food and water at night.

The man, who fought under the nom de guerre ''Comrade Disaster'' and whose real name is William Bonga, was found Nov. 11 and handed over to police by the hunters, according to the Herald.

The newspaper, published in Harare by the state-owned Mass Media Trust, said Bonga was passed on to the army and finally to the headquarters of the ruling Zimbabwe African National Union.

It said Bonga was a member of ZANU's military wing before Zimbabwe, formerly the British colony of Rhodesia, became independent in 1980. The Zimbabwe African National Union came to power after winning 1980 elections

The Herald described Bonga as a short, fit man who seemed unaffected by his eight years of solitude. It said he did not know his age.

Bonga joined ZANU's guerrilla force in 1977 at a base in Mozambique and in 1978 was sent on his first operation into Zimbabwe, the Herald said.

''There was a heavy storm one day soon after we crossed (the border) and we dispersed in different directions to seek shelter,'' Bonga told the newspaper.

He was quoted as saying he lost his rifle while struggling through the bush and took refuge in the cave, fearing he would be caught by security forces of Zimbabwe's pre-independence white regime.

Throughout his years in the cave, he thought the war was continuing because he heard gunshots from a nearby military firing range, the Herald said. It said his food consisted mostly of baobab fruit and sorghum collected at night.

The newspaper said Bonga would receive the same demobilization payments as any other former combatants.