Less than a year ago, Venezuelan President Carlos Andres Perez commissioned a poll of U.S. public opinion. He learned that the vast majority of Americans had never heard of him, and had no idea where his country was located.

Since then, Perez has made two trips to the White House, and Rosaylnn Carter stopped here on her Latin American swing last summer.

On Tuesday, President Carter, who has called Perez "one of my best personal friends," will make Venezuela the first stop on his four-nation Third World tour.

While the trip may not clear up Americans' fuzzy ideas about this developing stridently democratic country that is one of their primary oil suppliers, it will cement a government-to-government relationship that has become one of the strongest in the hemisphere.

In an interview last week at Miraflores, Venezuela's executive office building, Perez said that Carter had "opened a new perspective in hemispheric relations" based on "ethical values" and mutual respect.

Yet, while he praised Carter's good intentions, Perez made it clear that he expects this week's visit to result in concrete U.S. support of economic growth in Latin America.

"We are not meeting out of courtesy," Perez said. "Until now, of course, what Carter has done has no practical value; one can't point to concrete accomplishments."

The United States, he said, is still buying raw materials from the Third World cheaply and selling its technology and manufactured good at a high price.

"The sincerity of the United States is going to be put to the test in the next few months," he said.

The unusually close relationship between the United States and Venezuela that provides Perez the freedom to sepak candidly to Carter has weathered several tests in the recent past.

It survived the 1976 Venezuelan nationalization of U.S. oil interests here in the American press that Perez was once on the CIA payroll.

It has grown despite Perez' continuing condemnation of U.S. multinationals and U.S. economic domination of the Third World, and his recent support of a worldwide oil price increase to compensate for that domination.

Along with the criticism, however, Perez has aligned his government unswervingly with Carter's concern for human rights around the world and Venezuela has become Latin America's most outspoken defender of civil liberties. It has also endorsed Carter's call for curbs on potential nuclear proliferation in the hemisphere.

When Perez talks of the support he wants from Carter for economic development in the hemisphere, he specifically mentions a commitment of money and technology for the Latin American Economic System. That is an organization designed to promote Latin American-owned and operated multinational industries.

Without that commitment, Perez will have a hard time justifying his continued outspoken support for the United States.

Perez also wants to talk about "the complicity of North American and European companies with the racist groups in South Africa," and the subject closest to his heart - the stalled North-South dialogue over economic balance between the developed and developing worlds.

With the exception of the latter, none of these issues holds a prominent place on Carter's Venezuela agenda.

There is little doubt, however, that Perez will agree with Carter's position on most items that the U.S. president wants to discuss: Lowering U.S. energy consumptio (thus stretching the life span of Venezuela's oil reserves), avoidance of regional confrontations in Latin America, lessening of U.S. influence and financial support in the Organization of American States. In addition, these is the question of remaining compensation due nationalized U.S. companies and that of unified pressure against the Nicaraguan dictatorship of Anastasio Somoza.

In many ways, the warmth of the Carter-Perez relationship stems from the personal and political similarities between the two men.

Like Carter, Perez, 55, is a country boy, raised on a coffee farm in the Andes. Like Carter, he is known to be a man of boundless energy, an early riser who is demanding of his subordinates.

Perez smiles a lot in public, but he is known to have a quick and occasionally ruthless temper in private. While he maintains an extremely open relationship with the Venezuelan press, he is easily wounded by media attacks and has been known to overreact to them.

A member of Venezuela's largest political party, Perez, like Carter, surrounds himself with aides whose loyalty is first to him and second to the party. He has been accused of turning a blind eye to the failings of those personal loyalists.

His political opponents say Perez has concentrated his energy on flashy foreign policy objectives to the detriment of urgent domestic programs.

The fourth president in a 20-year string of democratically elected leaders, Perez came to office in early 1974 with the largest mandate in Venezuela's history. Unlike Carter, he has been politician all of his life. At age 15, he became active in the Democratic Action Party begun 50 years ago by Venezuelan political patriarch Romulo Betancourt.

Perez comes by his defense of human rights honestly. He spent the 10 years between 1948 and 1958 imprisoned or exiled by a military dictatorship.

When democratic forces overthrew Gen. Marcos Perez Jimenez, Perez returned to Venezuela to take an active part in Betancourt's party, a worker-and peasant-based group with ties to European Social Democrats.

Perez' critics count his term as interior minister under the Betancourt presidency in the early 1960s as a black mark on his liberal record. They sai he used a combination of militarist and McCarthyite tactics against suspected Communists in the government. They hold him responsible for the death or firing from goverment jobs of hundreds of such individuals.

Elected to a five-year presidential term after a decade of party stewardship, Perez controls a yearly national income bigger than that of all his elected predecessors combined. The 1974 quadrupling of world oil prices have multipled Venezuela's assets and Perez found himself with what was called an "unprecedented historical opportunity" to bring an undeveloped country into the modern world.

While opponents charge, and Perez does not deny, a high level f official corruption and waste, most observers agree that his successes in building a "new Venezuela" with a diversified industrial base and more equal distribution of income have outnumbered his failures.

"We have been at the same time audacious - in the nationalization of the oil and iron ore industries - realistic and prudent," Perez said.

One of the most prudent things the Perez government did, observers say, was the establishment of the billion dollar Venezuela Investment Fund, an overseas bank account this is both a nest egg for the future and a Third World lending institution.

Soon after taking office, Perez established relations with the Communist bloc countries, apparently overcoming his formerly strong anticommunism. He has traveled to most of the OPEC countries, to the Soviet Union and much of Latin America.

His critics say that Perez has become a publicity seeking, Third World gadfly in the manner of former Mexican president Luis Echevarria.

But Perez maintains that integration, through regional industries, and the presentation of a united economic front to the developed nations on trade issues is the only hope for both Venezuela and the entire Third World.