James C. Hagerty, 71, a quick-witted, quick-tempered and cool-nerved former newspaperman who was a trusted presidential adviser while serving as White House press secretary throughout the Eisenhower administration, died yesterday in Bronxville, N.Y.

Mr. Hagerty, an American Broadcasting Co. executive for 14 years after leaving the White House, died at 5:45 p.m. after being admitted to a hospital Friday with chest pains. The cause of death was not immediately known.

A witness to great events and a participant in major decisions, Mr. Hagerty was respected as news secretary for his skill in steering a course between the reticence demanded by policy and policy-makers and what he recognized to be the public's right to know.

When Mr. Eisenhower suffered a heart attack in 1955, he demonstrated his trust in Mr. Hagerty with the instruction: "Tell Jim to take over."

The news secretary was credited with the decision to quell rumor, confusion, and fears of political and national vulnerability by providing all available facts. In the wake of this policy, the nation had little difficulty in accepting Mr. Eisenhower as a candidate for reelection in 1956, and indeed, Mr. Hagerty was described as one of the inner circle of advisers who persuaded the president to run again.

An innovator in introducing television to presidential news conferences, and permitting direct quotation of the president, Mr. Hagerty, like other adept practitioners of his art, could tailor policy to circumstance.

"I work for the president, don't I?" he sometimes reminded reporters who persisted in seeking information Mr. Hagerty preferred not to disclose.

His abilities were recognized in a light-hearted way in 1961 when he was presented the Legion of Honor at the French Embassy.

"All that you say is true -- but you don't, of course, tell all of the truth," the French ambassador said.

Mr. Hagerty was born in Plattsburgh, N.Y., and after graduating from Columbia University, followed in the footsteps of his father by joining the New York Times and become a political correspondent.

His coverage of New York state government attracted the attention of the state's governor, Thomas E. Dewey, and in 1943 he became Dewey's press secretary. After working for Dewey in two unsuccessful presidential campaigns, he was loaned to the Eisenhower campaign in 1952.

Mr. Hagerty, who enjoyed the heat of the political kitchen, was able to withstand Mr. Eisenhower's occasional angry outbursts and that, along with his keen political knowledge, helped win the president's trust.

"You don't scare easily do you?" the president observed early on. "No sir," said Mr. Hagerty, a stock, bespecled men, "I don't."

In addition to providing advice on public relation matters, Mr. Hagerty made his views known internally on political issues, particularly in the domestic area, and was said to be one of the strongest advocates in the White House of civil rights meaures.

Part of his job came to be traveling around the world making arrangements for future presidential visits. On such a trip in 1960, his reputation for unflappability was tested when the car he was riding in was trapped in Japan for 20 minutes by anti-American demonstrators. The proposed visit was canceled.

As news secretary Mr. Hagerty exerted absolute control over access by reporters to White House aides. He was also versed in the use of relying to undesired questions with "no comment."

Not unaware of his own practices, he took particular delight after joining ABC as a news executive, in announcing the instructions he would give give to his reporters: "Get the news and don't take no for an answer."

He and his wife had two sons.