Jack Alexander was born 7 December 1930 in Iola, Kansas to Mr. and Mrs. Floyd Alexander. He graduated from Topeka (Kan.) High School in 1949, where he captained the school's last segregated basketball team, and attended Washburn University for two years before serving in the United States Navy from 1952-1956. In 1951, Alexander began at the Goodyear Tire and Rubber Company in Topeka; he continued to work for that Company until his 1985 retirement. In 1973, Topekans elected Alexander Topeka's Water Commissioner, making him one the first Topekan African American elected to a city office. During his time on the Topeka City Commission, Alexander also served on the Kansas Water Authority (1981-1985). He remained Commissioner until 1985 when he began work as a manager of permits, compliance, and enforcement at the Kansas Department of Health and Environment's Department of Water. After five years at KDHE, Alexander worked from 1990-1991 as a legislative liaison within the Office of the Governor. At that time, he also served the city of Topeka on the City Council. Appointed to the Kansas Corporation Commission in 1991, Alexander became the first minority appointed to that body. In 2003, Alexander ran for Topeka Mayor and, in 2004 Governor Sebelius appointed him temporary State Fire Marshal.

Along with his numerous positions, Alexander also has been involved in numerous organizations. He served as Vice President of the NAACP's Topeka Chapter and the United Way of Topeka; he also served on the Board of Stormont-Vail Regional Medical Center and as President of the Board of the Shawnee County Community Assistance and Action, Inc.

Alexander married Tillie Simon; the couple had four children.