Bradford Lee Gilbert (March 24, 1853 – September 1, 1911) was a nationally active American architect based in New York City. He is known for designing the Tower Building in 1889, the first steel-framed building anywhere and the first skyscraper in New York City. This technique was soon copied across the United States. He also designed Atlanta's Cotton States and International Exposition of 1895, the Flatiron Building in Atlanta, and many railroad stations.

Bradford was born in Watertown, New York, the son of civil engineer and banker Horatio Gates Gilbert and his wife Marie Antoinette (née Bacon). His uncle was Jasper W. Gilbert, a justice with the New York Supreme Court.

He attended Siglar's School in Newburg and the Sedgwick Institute in Great Barrington, Massachusetts. Later, he had private tutors at home in Irvington, New York to get ready to attend Yale University, rather than his father's alma mater Norwich University. However, Gilbert decided to forgo college as he was very anxious to learn architecture. He became a student with the architectural firm J. Cleveland Cady in New York City for five years, beginning in 1872.

In 1876, Gilbert was hired as an architect for the New York, Lake Erie and Western Railroad, under engineer Octave Chanute. Through his work with the railroad in the northern and northwestern states, Gilbert earned a reputation for originality. Although his body of work is diverse, he preferred Romanesque style and consistently featured "sinuous, interlaced patterns, virtuoso brickwork and deep red color effects".

By 1890, Gilbert opened a firm in his name at 1 Broadway in New York City, initially specializing in railroad and public buildings. He said, "It certainly costs no more, often not such much, to design a building that is architecturally correct, of good, quiet contour, the whole effect gained by constructional outlines, in place of the fancy 'ginger-bread' work too often adopted; and with the interior arrangements designed to meet every requirement."

Throughout his career, Gilbert also designed apartment buildings, churches, clubs, exhibition buildings, hospitals, hotels, houses, and office buildings. Gilbert did not just design buildings, he also managed the projects and visited the construction sites; this was documented in newspapers articles announcing his arrival in town to check on the progress of the projects.

This attention to detail may have paid off as many of his other projects steamed from his railroad connections, including designing residences for William H. Baldwin Jr. who was president of the Long Island Railroad, Alfred Skitt who was president of the New York City Interborough Railway Company, Arthur M. Dodge whose father built the Macon and Brunswick Railroad, Benjamin A. Kimball who was president of the Concord and Montreal Railroad Company, and William Greene Raoul president of the Atlantic and Birmingham Railway, the Central Railroad and Banking Company of Georgia, the Mexican National Railroad Company, and the Southwestern Railroad.

As an architect with the New York, Lake Erie & Western Railroad, Gilbert designed many railroad stations and related buildings. Through his private practice, his railroad clients included the Atlantic Coast Line Railroad; Boston & Maine Railroad; Central Railroad of New Jersey; Concord and Montreal Railroad; the Delaware, Lackawanna & Western Railroad; Flint & Pere Marquette Railroad; Georgia Railroad Company; Grand Rapids and Indiana Railroad; Illinois Central Railroad; Intercolonial Railroad (Canada); Michigan Central Railroad; Missouri-Kansas-Texas Railroad; New York, New Haven and Hartford Railroad; Norfolk and Virginia Beach Railroad; Northern Pacific Railway; Old Colony Railroad; Philadelphia & Reading Company and others. In 1901, he designed the Ottawa Central Railway Station. He also designed stations, offices and terminals for the National Railroad of Mexico.