Elks National Memorial is a traditional Beaux-Arts design, with rich classical elements throughout the exterior and interior. Following the Beaux-Arts style, the building features exact symmetry across its domed temple and two protruding wings, heavy use of columns, a decorative frieze, and a grand staircase entrance. These are many of the characteristics that defined American Beaux-Arts, inspired by the design principles of Ecole des Beaux-Arts in Paris. Often, American Beaux-Arts was employed for monumental buildings designed for government use or memorials.

“Elks War Memorial, Chicago” by Boston Public Library is licensed by CC BY 2.0

The Elks National Memorial stands 115 feet tall, equivalent to a ten-story building. The entirety of its exterior is made of gray Indiana limestone, including the front steps and building itself. The sole front entrance to the building is a large, arched bronze doorway with an intricate design, placed directly in the center of the building. The central pavilion is topped with a colonnade of 24 columns. Directly above the entrance and below the colonnade is a frieze by Adolph Weinman, titled "The Triumphs of Peace Endure - The Triumphs of War Perish" which extends around the entirety of the building. Behind the colonnade are carved stone panels by Gerome Brush.

The north and south wings of the building frame the central pavilion, creating an 'E' shape. At the ends of these wings are sculptures by Weinman, Patriotism and Fraternity. Atop these wings are massive stone urns.

The interior of the building is even more ornate and luxurious. Within the rotunda, there are 27 varieties of marble, sourced from across the United States, as well as Austria, Belgium, France, Greece, and Italy. The rotunda has two tiers of columns. The first tier, starting from the floor, is composed of 48 light-colored Doric columns, as well as eight darker Ionic columns with gilded tops. These Ionic columns frame four separate wall niches, spaced around the rotunda, that each hold a gilded bronze sculpture by James Earle Fraser.

Above this first tier colonnade is an architrave, a red marble band that connects the columns together. It is broken by the eight arches that frame the eight entrances around the rotunda. Above the architrave is a carved marble frieze, made of a cream-colored marble sourced from Virginia, which is used heavily outside of the rotunda as well. The second tier colonnade is composed of 24 Corinthian columns in darker but varied colors. Half of the spaces between these columns are large art glass windows, while the other half are panels, filled with allegorical mural paintings by Eugene Savage. The ceiling is a gilded dome with five rows of octagonal coffering that get smaller as they approach a central oculus skylight.

Two of the corridors in the rotunda lead to the building's wings, and another leads to the Grand Reception Room, an equally opulent interior space that was built for the president of the Elks. Within this room are three murals by Edwin Blashfield. The room also holds four bronze and crystal chandeliers, oak paneled walls sourced from England and Scotland, and three large art glass windows. The room is 30 by 70 feet, with a ceiling that reaches 35 feet in height. The arched, paneled ceiling is elaborately decorated with intricate molding around the panels.