Milan J. Hasal, 54, a World Bank official since 1961 and a resident here since 1948, died at his home in Washington Monday following a heart attack.

Mr. Hasal was born in Prague, Czechoslovakia. During World War II, he served as a lieutenant in the Czechoslovak Home Army intelligence brigade against the Germans.

After the assassination in May 1942, of Reinhard Heydrich, the notorious SS official, Mr. Hasal and members of his family were taken hostage by the Nazis. He escaped from a concentration camp in April 1945, and continued to work in the underground for the final month of the war. He received the Czech War Cross.

After the war, Mr. Hasal entered the Czechoslovakian Military Academy and became an army lieutenant.

Following the Communist takeover in Czechoslovakia in 1948, Mr. Hasal, his father, Gen. A. B. Hasal, a former Czechoslovakian minister of transportation, his mother and two sisters fled the country and came to the United States.

They settled in Washington, and Mr. Hasal attended American University, from which he graduated. He worked for the American Security & Trust Co. before joining the World Bank, where he became an examiner in the bank's treasury department.

Survivors include his wife, the former Grethe Pedersen, and two daughters, Karin and Dana, all of the home in Washington; a son by a previous marriage, George Salvo, of Alamosa, Colo.; his mother, Mrs. A. B. Hasal, of Washington, and two sisters, Dagmar White, of Vienna, and Milica Svehla, of Silver Spring.

The family suggests that expressions of sympathy be in the form of contributions to a charity of one's choice.