The president of the national fraternity is known as the Grand Polemarch, who assigns a Province Polemarch for each of the twelve provinces (districts/regions) of the nation. The fraternity has many notable members recognized as leaders in the arts, athletics, business, civil rights, education, government, and science sectors at the local, national and international level. The Kappa Alpha Psi Journal is the official magazine of the fraternity since 1914. The Journal is published four times a year in February, April, October and December. Frank M. Summers was the magazine's first editor and later on became the Fourteenth Grand Polemarch. The current editor of the magazine is Dr. Keflyn X. Reed.

Kappa Alpha Psi sponsors programs providing community service, social welfare and academic scholarship through the Kappa Alpha Psi Foundation and is a supporter of the United Negro College Fund and Habitat for Humanity. Kappa Alpha Psi is a member of the National Pan-Hellenic Council (NPHC) and the North-American Interfraternity Conference (NIC). The fraternity is the first predominantly African American Greek-letter society founded west of the Appalachian Mountains still in existence, and is known for its "cane stepping" in NPHC organized step shows.

The founders of the Kappa Alpha Psi Fraternity, Inc. are pictured below and were: Dr. Elder Watson Diggs, most affectionately known as 'The Dreamer', Dr. Ezra D. Alexander, Dr. Byron Kenneth Armstrong, Atty. Henry Tourner Asher, Dr. Marcus Peter Blakemore, Paul Waymond Caine, George Wesley Edmonds, Dr. Guy Levis Grant, Mr. Edward Giles Irvin, and Sgt. John Milton Lee:

The founders endeavored to establish the fraternity with a strong foundation before embarking on plans of expansion. By the end of the first year, the ritual was completed, and a design for the coat of arms and motto had begun.

The fraternity was founded as Kappa Alpha Nu on the night of January 5, 1911 by ten African-American college students. The decision upon the name Kappa Alpha Nu may have been to honor the Alpha Kappa Nu club which began in 1903 on the Indiana University campus, but there were too few registrants to assure continuing organization.

During this time there were very few African-American students at the majority white campus at Bloomington, Indiana and they were a small minority due to the era of the Jim Crow laws. Many African-American students rarely saw each other on campus and were discouraged or prohibited from attending student functions and extracurricular activities by white college administrators and fellow students. African-American students were denied membership on athletic teams with the exception of track and field. The racial prejudice and discrimination encountered by the founders strengthened their bond of friendship and growing interest in starting a social group.

By 1913, the fraternity expanded with the second undergraduate chapter opened at the University of Illinois—Beta chapter; then the University of Iowa—Gamma chapter. After this, Kappa Alpha Psi chartered undergraduate chapters on Black college campuses at Wilberforce University—Delta Chapter, and Lincoln University (Pennsylvania)—Epsilon Chapter. In 1920, Xi Chapter was chartered at Howard University. In 1921, the fraternity installed the Omicron chapter at Columbia University, its first at an Ivy League university. The fraternity's first chapter in the South was established in 1921 at Morehouse College— Pi Chapter. Kappa Alpha Psi expanded through the Midwest, South, and West at both white and black colleges.

Some believe the Greek letters Kappa Alpha Nu were chosen as a tribute to Alpha Kappa Nu, but the name became an ethnic slur among racist factions. Founder Elder Watson Diggs, while observing a young initiate compete in a track meet, overheard fans referring to the member as a "kappa alpha nig", and a campaign to rename the fraternity ensued. The resolution to rename the group was adopted in December 1914, and the fraternity states, "the name acquired a distinctive Greek letter symbol and KAPPA ALPHA PSI thereby became a Greek letter Fraternity in every sense of the designation." Kappa Alpha Psi has been the official name since April 15, 1915.

In 1947, at the Los Angeles Conclave, the National Silhouettes of Kappa Alpha Psi were established as an auxiliary group, which membership comprises wives or widows of fraternity members. In 1980, the Silhouettes were officially recognized and granted a seat on the Board of Directors of the Kappa Alpha Psi Foundation. Silhouettes provide support and assistance for the activities of Kappa Alpha Psi at the Grand Chapter, Province and Local levels.

In the 1950s, as black Greek-letter organizations began the tradition of step shows, the fraternity began using the "Kappa Kane" in what it termed "cane stepping." In the 1960s, the cane was decorated with the fraternity colors. In the 1970s, it was shortened so brothers could "twirl" and tap the cane in the choreography with high dexterity. The national organization did not condone the use of canes in step shows and contended that "the hours spent in step practices by chapters each week would be better devoted to academic or civic achievement." Senior Grand Vice Polemarch Ullysses McBride complained about the vulgar language and obscene gestures sometimes engaged in by cane-stepping participants.