Donald L. Shell (March 1, 1924 – November 2, 2015) was an American computer scientist who designed the Shellsort sorting algorithm.

He acquired his Ph.D. in mathematics from the University of Cincinnati in 1959, and published the Shellsort algorithm in the Communications of the ACM in July that same year.

After acquiring his degree he went into the Army Corps of Engineers, and from there to the Philippines to help repair damages during World War II.

After acquiring his Ph.D., Shell moved to Schenectady, New York, to become Manager of Engineering for General Electric's new Information Services Department, the first commercial enterprise to link computers together using the client–server architecture.

He worked with John George Kemeny and Thomas Eugene Kurtz to commercialize the Dartmouth Time-Sharing System in 1963.

In 1971 Shell wrote "Optimizing the Polyphase Sort" in the Communications of the ACM, and in 1972 he joined with a colleague, Ralph Mosher (who designed the walking truck), to start a business, Robotics Inc., where he was the General Manager and chief software engineer.