Retired Navy Capt. Finn Ronne, 80, a veteran of 14 polar expeditions beginning with Adm. Richard E. Byrd's second Antarctic expedition, died Saturday in his home in Bethesda after a heart attack.

Capt. Ronne served as a seaman in the barkentine Bear aboard the 1933 expedition's journey to the Antarctic continent, then was a ski expert, surveyor, radio operator, and dog driver at Little America, Adm. Byrd's site.

Capt. Ronne was a recipient of the Second Byrd Antarctic Expedition Medals, which were awarded to "express the high admiration in which the Congress and the American people hold their heroic and undaunted accomplishments for science, unequaled in the history of polar exploration."

He returned to Antarctica with Byrd in 1939, this time as the expedition's chief of staff and executive officer. More than 1,000 new miles of coastline were explored, with Capt. Ronne traveling 450 of those miles with another companion on an 84-day trek.

In 1947 he returned to the Antarctic as head of a scientific expedition under the auspices of the American Geographical Society to study the then unexplored Weddell Coast Territory.

Capt. Ronne and 22 associates landed at Marguerite Bay near the Palmer Peninsula on March 13, 1947. His group charted Marguerite Bay and traveled farther south than any other group had ventured in that section of Antarctica. Three expedition airplanes viewed more than 15,000 square miles of Weddell Sea area never seen before.

By the following March, they had finished charting the Weddell Sea coastline, the last uncharted coastline in the world. Part of the land the party discovered was named "Edith Ronne Land," in honor of Capt. Ronne's wife, who accompanied him on this trip and became the first woman to set foot there and to winter in Antarctica.

Mrs. Ronne also contributed articles on the Ronne expedition to the North American Newspaper Alliance detailing the story of 700,000 square miles the party covered by trimetrigon photography and detailing the 90 new place names given.

During the five trips to the Arctic, Capt. Ronne helped lay the groundwork for Thule Air Force Base in Greenland. His later posts included those of military and scientific leader of Ellsworth Station in Antarctica during the International Geophysical Year from 1957 to 1958, and as postmaster of Oleana Base in Antarctica.

Capt. Ronne was the author of four books on Antarctica. His awards included the Explorers Medal and the Royal Norwegian Order of Saint Olav. He also received the Legion of Merit and had served in the U.S. Navy during the World War II. He retired from the Navy in 1961 with the rank of captain.

Capt. Ronne was a native of Horten, Norway. He earned degrees in naval architecture and marine engineering at Horten Technical College before coming to this country as an engineer with the Bethlehem Ship Building Company in Elizabeth, N.J., in 1923.

Capt. Ronne's father, Martn Richard Ronne, accompanied Roald Amundsen on the expedition at the turn of the century which discovered the South Pole.

Capt. Ronne's father also traveled to Antarctica in Byrd's first expedition, but died before the second began. During Capt. Ronne's stint as Byrd's chief of staff in the late 1930's, a bay in Antarctica was named in honor of the elder Ronne.

Capt. Ronne was a life member of the American Geophysical Union, and had been chairman of the American Antarctic Association, board member of the Arctic Institute, honorary vice president of the American Polar Society.

In later years, he has served on the board of directors of the Explorers Club of New York, been a consultant to the Defense Department, and lectured in Europe for the State Department.

He had lived in this area for more than 40 years.

In addition to his wife of 35 years, of Bethesda, he is survived by a daughter, Karen Ronne Tupek of Washington, and two brother, John and Rolf, both of Norway.

The family suggests that expressions of sympathy be in the form of contributions to the Finn Ronne Memorial Fund for Polar Exploration, c/o the Explorers Club, 46 East 70 Street, New York City, 10021.