Nancy Land Gager, 48, an area author and editor who in the early 1970s was the founding president of the Washington chapter of the National Organization for Women (NOW), died of leukemia Friday at Johns Hopkins Hospital in Baltimore.

Miss Gager was the author of a number of feminist works, including the script for "How We Got The Vote," an Emmy Award-winning docmuentary narrated by Jean Stapleton, which appeared in 1976.

Miss Gager also was an author and the editor of the "Women's Right Almanac," which was first published in 1974.

A review in The Post said, "This 620-page almanac is a remarkable document, balanced, interesting and well-informed. It contains an extraordinary amount of substantive information." The book was reprinted in 1975 and 1976 and hailed as an "outstanding reference work" by the American Library Association.

Among her other works was "Sexual Assault: Confronting Rape in America," which was written with Cathleen Schurr and is used by the government's National Rape Crisis Center.

She also had written books about the Kennedy family, which included psychological studies of that political family and its women.

Miss Gager was a native of Washington and a graduate of Woodrow Wilson High School. She graduated from Wellesley College with a bachelor's degree in political science in 1953 and studied literature at Oxford University.

She also spent time climbing mountains in the Himalayas in Nepal and as a civilian intelligence analyst with the Army in Korea before returning to Washington.

She was on the staff of the "National Georgraphic" and was a contributing editor of "The Georgetowner" from 1959 to 1962.

During the 1970s she was editor of the LEAA Newsletter and was president and editor of the Elizabeth Cady Stanton Publishing Company in Bethesda.

Among the publications to which she contributed articles were The Chicago Tribune, the Washingtonian, and the Armed Forces Journal.

In addition to NOW, Miss Gager belonged to the American Historical Association, and the Association for Women in Psychology.

Miss Gager was a resident of Gaithersburg.

Her marriage to William B. Clinch ended in divorce.

Survivors include two daughters, Lucia and Tyler Clinch, and a sister, Corinne Vincelette, all of Gaithersburg; her mother, Grace Gager of San Jose, Calif., and two brothers, Robert Gager of Saratoga, Calif., and Charles Gager of Sunnyvale, Calif.

The family suggests that expressions of sympathy be in the form of contributions to the National Organization for Women's Legal Defense Fund.