South African forces entered Angola last weekend and killed at least 201 black nationalist guerrillas at a base there, the South African Defense Force announced today.

According to a defense force statement, the attack took place Saturday, 14 miles across the border between Angola and Namibia (South-West Africa) in an area west of the main zone of guerrilla warfare where South Africa has launched other raids.

The statement said a unit of 45 commandos from the crack 32d Battalion landed by helicopter and took the guerrillas of the South-West Africa People's Organization (SWAPO) by surprise, killing 201 of them. Three South Africans were also killed during the raid, according to the statement. Most members of the 32d Battalion are black, and an officer told journalists flown to the scene of the battle today that one of the dead was black.

Capt. Jan Hougaard, who led the task force, said his men captured tons of supplies, 90 Soviet-made AK47 assault rifles and more than a thousand grenades and land mines. He said the camp was apparently a temporary supply base with no permanent buildings and no fortifications.

Hougaard said most of the ammunition was imported from the Soviet Union in December via the Angolan port of Mocamedes and was being stockpiled for guerrilla assaults on Namibia.

Hougaard said "a lot" of the food in captured supply caches came from the U.S.S.R. Aid and Relief Fund, France and Denmark. It included corned beef from Zimbabwe, he said.

Maj. Gen. Charles Lloyd, Army commander in Namibia, said the cans of corned beef were evidence that Zimbabwe is aiding the guerrillas.

The Zimbabwean government of President Robert Mugabe says that while it supports anti-South African guerrilla movements politically, it does not give them material aid, because Zimbabwe is too vulnerable to military and economic reprisals from its more powerful white-ruled southern neighbor.

Lloyd said it was clear there was "close contact" between SWAPO leaders and the Zimbabwean government.

"I think one can assume that there will be support as well--arms, foodstuffs," said Lloyd.

"I think one can accept that foodstuffs are coming from Zimbabwe to Angola for SWAPO. And I think they also exchange a lot of ideas--lessons learned from the Zimbabwe war."

In a telephone interview from Windhoek, Lloyd would not give other evidence of Zimbabwean support for the rebels.

"I am not going to disclose my sources of information," he said, "but I obviously did not suck those words out of my thumb."

Zimbabwe's director of information, Justin Nyoka, said his government was studying Lloyd's remarks and would issue a statement Wednesday.

Derek Bensley, managing director of the company that manufactured the corned beef, Liebigs Ltd., of Bulawayo, expressed surprise tonight at Lloyd's statement.

"Most of our stuff is sold locally," he said, "but a little goes out to other African countries like Zaire and Angola.

"I think it is rather jumping to conclusions that this is official aid, because those cans could have arrived there by ordinary commercial channels."

Journalists flown to the site of the raid in the Cambeno Valley, across the Cunene River in the Iona National Park, reported seeing decomposing corpses strewn about the camp in the intense tropical heat.

Lloyd said the raid demonstrated to the territory's inhabitants that the Army was determined to protect them from "SWAPO terrorists."

"The SWAPO buildup that led to the operation shows the clear intention of SWAPO and the Soviet Union to continue with the war, while SWAPO and certain black African nations are publicly advocating the signing of a cease-fire," he said. "It has been proved to us that SWAPO cannot be trusted."

Hougaard said his men were ferried from Namibia by helicopter to about one mile from the base and at first met little resistance.

The SWAPO guerrillas fought back with Soviet-made SA7 missiles, but the firing was erratic and was no threat to the South Africans, he said.

South Africa has been involved for 15 years in a war against SWAPO, which is fighting to end the Pretoria government's control of the former German colony that it has administered since World War I.

While the United States has led a peace initiative with other Western powers to try to find an agreed formula for elections leading to independence, the war has continued sporadically.

Beginning in August, South Africa has been carrying the war to SWAPO with a series of attacks on the guerrillas' bases in Angola.

Some of these raids have resulted in claims of up to 1,000 guerrillas killed, and in two of them South African troops have remained in occupation of large parts of southern Angola for as much as a week.

By those standards, Saturday's seven-hour raid was brief and comparatively small.