Sen. Barry Goldwater (R-Ariz.) has completed a 10-day campaign of criticism of the Carter administrator's African policy in South Africa, providing a welcome balm to the Pretoria government that feels it has suffered from its deteriorating relationship with the United States.

Goldwater, who ended his university-sponsored tour this past week-end, accussed Carter of "too much meddling" in South Africa, and he promised that a Republican administration would lift the arms embargo against this country.

Goldwater's remarks were a hopeful sign to the white South African government that the administration's Africa policy may become a major issue in this fall's U.S. elections. The South Africans believe that such a debate would reveal a vast reservoir of pro-South Africa sentiment in the American population.

A chief target of the conservative senator, who was making his third visit to South Africa, was U.S. Ambassador to the United Nations Andrew Young.

"Andy Young speaks only for Andy Young, although his position gives his words more credence than they deserve," Goldwater told a group of mostly Afrikaans-speaking white university students.

"Most Americans don't know why Carter tolerates him," he said. "If left to a vote, he would be ousted by an overwhelming landslide."

Goldwater said in a broadcast interview that Ambassador Young lacked support in the United States, particularly in Congress. He said even members of Congress from Young's home state of Georgia oppose him, "not because he's black, but because he's said the wrong things.

"I don't think many of the black people [in the United States] even look on Andy Young as a black man," he said. "Have you ever seen him? He's not very black."

He also said on his trip that that Young has "no respect for the truth" and should "either shut up or come home."

Referring to the interim agreement signed by Prime Minister Ian Smith and three black nationalist leaders in neighboring Rhodesia, Goldwater told the student that "the U.S. and Britain should have led the world in acclaiming the progress" made in that country.

When asked if a Republican admistration would lift the arms embargo against South Africa, he replied, "I would say yes. I think I can promise that.

"Of course we have our own problems in the Republican Party, and we may get the wrong man in."

The United States has observed a voluntary arms embargo against South Africa since 1963 and the United Nations imposed a mandatory weapons boycott against the government of Prime Minister John Vorster last October.

Goldwater said he believed Carter's policy in Africa was the result of being misinformed. He said in a newspaper interview, "I think the man acts from very sincere motives, but I don't think he understands."