By SAM JACOBS Herald Staff Writer

Carlos Prío Socarrás spent the last 25 years of his life in political exile, fighting first one and then a second dictator of Cuba.

The last constitutionally elected president of Cuba, Prío was overthrown by Fulgencio Batista in March, 1952. For the next seven years, from his exile in Miami. Prío strongly opposed Batista - with words, with hundreds of thousands of dollars and, when the time was ripe, with rifles.

Then, after returning to Cuba briefly following Fidel Castro's government takeover in 1959, Prío broke with Castro, denouncing him as a tyrant.

HE CAME back to Miami and spent the rest of his life as outspoken an opponent of Castro as he had ever been of Batista.

Prío's death Tuesday ended a long and varied political career which took him from the University of Havana, where he led student protests against then-dictator Gerardo Machado in the early 1930s, to the presidential palace, to a position as one of the most respected of Miami's anti-Castro Cuban leaders.

Prío is believed to have come to Miami with a large fortune, much of which was spent to finance revolutionary activities against Batista and Castro. His political opponents in Cuba charged at the time that Prio's administration was riddled with graft, although the allegations were strongly denied by Prío.

A native of Pinar del Rio province, Prío first became politically active as a law student at the University of Havana. He became a follower of Dr. Ramón Grau San Martin, then a university professor, who was leading the opposition to Machado.

LATER, AFTER Grau was elected president in 1944, he named Prío labor minister. Four years later, Prío was elected president.

Prío took office on a wave of popularity, enhanced by his announcement in his inaugural speech that he had ordered all retail prices cut by 10 per cent.

Dr. Luis Aguilar, a Cuban-born history professor at Georgetown University in Washington, D.C., said Prío worked to increase the wages of laborers and to improve economic relations with the U.S.

Aguilar added that Prío was "a very open president. There was absolutely unrestricted freedom of the press and no one was persecuted."

PRÍO BECAME known as "the cordial president," but maybe he was too cordial, Aguilar said. He permitted former dictator Batista, then living in exile in Daytona Beach, to return to Cuba and even provided him with a bodyguard. A short time later, Batista overthrew Prío in a bloodless coup.

From his base here, Prío - a distinguished-looking gray haired man with a preference for dark glasses - was a leading opponent of Batista. He was twice indicted on charges of violating U.S. neutrality laws by fomenting revolution in Cuba, either by smuggling in arms or financing the revolutionary activities of others. One charge in 1956 netted him a $9,000 fine; another, in 1959, two years' probation.

In one of the cases, he was charged with giving $240,000 to some supporters to buy arms. Ironically, the supporters said, they were robbed of the money a short time later in Fort Worth, Tex.

Prío helped finance the Castro revolution, according to news accounts of the period. In addition, a small army of Prío supporters was active in Cuba not long before the ouster of Batista.

PRÍO RETURNED to Cuba after the revolution, even though Castro didn't make him a part of the new government. As late as a year and a half later, he was telling reporters in Miami that "Castro is my friend."

But a few months later, he broke with Castro and returned to exile here. For several years after that, Prío was prominent in Cuban exile politics in Miami. At one point he even tried to set up an official government in exile, but the attempt failed.

Prío also mended some fences with his old enemies, the Batista followers, if not with Batista himself. Among those he became friendly with was Andrés Rivero Aguero, who was elected president under Batista's sponsorship in 1958 but who was prevented by the revolution from taking office.

In recent years, Prío stayed more and more in the background, while still maintaining the wide respect of the Cuban community.

IN 1974, however, he led an 11-person delegation to an Organization of American States meeting in Ecuador to protest a proposed OAS move lifting sanctions against Cuba. Although the delegation wasn't permitted out of its hotel, OAS members rejected the proposal and the delegation returned home in triumph.

"I have not been so happy in 40 years," Prío told a huge crowd at Miami International Airport.

Then, on Feb. 26 this year, Prío was one of seven Cuban exile leaders who met with Secretary of State Cyrus Vance in an attempt to dissuade him from re-establishing ties with the Castro government. The meeting was set up largely by Prio's son-in-law, Florida Democratic Party Chairman Alfredo Durán.

A few months before that, Prío and Rivero Aguero had surprised many of their old friends here by issuing a statement in support of Jimmy Carter in the presidential election.

PRÍO'S DEATH came as a shock to his old political associates now living in the United States.

"It was a terrible loss to all Cuban people," added Eduardo Suarez-Rivas Jr., whose father, a former Cuban Senate president and agriculture minister, was one of Prío's closest friends.