The Rev. Harry J. Jaeger Jr., 60, pastor of Mount Vernon Presbyterian Church in Alexandria since 1972, died of a heart attack Tuesday.

He was stricken while attending a meeting of the National Capital Union Presbytery at the National Presbyterian Church in Washintgon and was pronounced dead at Georgetown University Hospital.

Mr. Jaeger was active in the National Capital Union Presbytery, the Mount Vernon Rotary Club and Ventures in Community (VIC), a local ecumenical religious organization.

He was born in Philadelphia. A graduate of Hampden Sydney College in Virginia, he earned a bachelor of theology degree from Princeton Theological Seminary in New Jersey and took postgraduate work in philosophy and education at the University of Delaware in Newark.

Mr. Jaeger had also served churches in Parkesburg, Pa., Trenton, N.J., Philadelphia, Milford, Del., Smyrna, Del., and Maui, Hawaii.

From 1945 to 1955, he was professor of Bible and general theology at the Philadelphia College of Bible, and from 1965 to 1970, associate professor of philosophy and religion at Wesley College in Dover, Del.

He wrote numerous articles for religious publications and was the author of four books, "Hidden Rocks," "Guide for Living," "The Easter Story" and "The Shepherd's Psalm." He was coauthor and editor of the position paper on eschatology, a branch of theology, adopted by the General Assembly of the Presbyterian Church of the United States in 1978.

He is survived by his wife, Dorothy, of the home in Alexandria; two sons, Steven, of Baltimore, and Colin Cooper, of Severna Park; three daughters, Eileen Dodd, of Georgetown, Del., Sally Falk, of Alexandria, and Jane Prados, of Maui; his mother, Ivy Montgomery Jaeger, of Fort Washington, Pa., and five grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Harry J. Jaeger Jr. Memorial Scholarship Fund in care of Mount Vernon Presbyterian Church.