The Penobscot Building was designed by Donaldson and Meier in the Beaux-Arts style, and incorporates brick and stone into its materials.

[1] Its building was financed by prominent Detroit businessmen, including lumberman Simon J. Murphy, Sr.

The lower three stories of the building are faced in limestone, the middle seven in brick, and the upper three in terra cotta.

Corinthian column piers front the eleventh and twelfth stories, and the original building cornice has been removed.

The present day use of the office building is primarily for retail shops and services.