William Neale Roach, 66, a former staff member and fund-raiser for the Democratic national and congressional committees, died Wednesday at Suburban Hospital of complications from emphysema.

He also was a former legislative representative for American Trucking Associations Inc., from which he retired in 1977. He continued to be a special consultant to the Trucking Operators Nonpartisan Committee until his death.

Mr. Roach, who was born in Chevy Chase, Md., began his career in politics while a student at St. John's College High School in Washington, when he became a part-time messenger for the Democratic National Committee in the 1928 Al Smith Presidential campaign.

Four years later, as a full-time staff member with the committee, he attended his first convention.It was held in Chicago and Franklin D. Roosevelt became the party's candidate for president. Mr. Roach often said later that it was then he realized he had "really been bitten by the political bug."

He moved up the party ladder to become assistant treasurer and worked on several national conventions. He later managed four conventions, those in 1944, 1948, 1952 and 1956, although he pulled out of the latter after a disagreement with Democratic National Chairman Paul M. Butler.

However, Mr. Roach, who earlier managed national headquarters for President Truman's reelection campaign in 1948 and who was assistant manager of Adlai Stevenson's 1952 presidential campaign, continued to be active in Democratic politics.

He was executive director of the Democratic Senatorial Campaign Committee in 1956, director of national Democratic congressional fund-raising dinners in Washington in the 1960s and director of public relations for the Democratic National Committee in 1965. He also was active in the 1961 and 1965 presidential inaugurals.

At the time of his death, he was president of the National Capital Democratic Club.

Speaker of the House Thomas P. O'Neill Jr., said of Mr. Roach's death:

"The Democratic Party has lost a real friend and a true believer in our party's policies and programs for the people."

After he resigned as convention manager in 1956 Mr. Roach set up his own consulting firm in public and government relations.

His clients included American Trucking Associations and he became a full-time legislative representative for ATA in 1971.

He is survived by his wife, the former Frances A. Spivey, of the home in Chevy Chase; four children, Louisa R. Menyhert, of Kill Devil Hills, N.C., Edith R. Buttinelli, of Bethesda, William N. Jr., of Tybee Island, Ga., and Edward M., of Gainesville, Va.,; four sisters Rosanne L. Christopher, Mary M. McCarthy and Helen J. Becker all of Bethesda, and Catherine E. Perrine, of St. Petersburg, Fla.; a brother, Richard E., of Atlanta, Ga., and 10 grandchildren. CAPTION: Picture, WILLIAM NEALE ROACH