200 Madison Avenue (also known as the Marshall Field Building, Astor Estate Building, International Combustion Building, and Tower Building) is a 25-story office building in the Murray Hill neighborhood of Manhattan in New York City. It is along the west side of Madison Avenue between 35th and 36th Streets. Designed by Warren and Wetmore, it was built from 1925 to 1926.

200 Madison Avenue's facade is largely made of red brick with limestone trim, as well as window spandrels made of terracotta and cast iron. The ground story is made of limestone and contains entrances from Madison Avenue, 35th Street, and 36th Street. The building contains a setback above its ninth story. The T-shaped lobby is designed in a neo-Renaissance style, with a north–south arcade connecting 35th and 36th Streets, as well as an elevator lobby extending toward Madison Avenue. The lobby's ornate interior contains gilded decorations and various animal motifs. Due to zoning restrictions on the eastern part of the site, the lower stories originally served as an apartment hotel, while the smaller upper stories contained offices.

Since the 1910s, the Astor family had wanted to develop a commercial building on the site, but the plans were delayed for a decade due to opposition from J. P. Morgan Jr. and other local residents. 200 Madison Avenue was developed by a syndicate that included Texas entrepreneur Jesse H. Jones. The building was originally known for its largest tenants, Marshall Field and Company and International Combustion. The apartment hotel initially occupied the second through ninth floors, but it was unprofitable, closed in 1939, and was turned into office space, with tenants such as Amtorg Trading Corporation. The building was sold several times in the 20th century, including to a group representing Philippine president Ferdinand Marcos during the 1980s. George V. Comfort and the Loeb Realty and Development Corporation acquired 200 Madison Avenue in the 1990s, and the New York City Landmarks Preservation Commission designated the building's lobby as an official landmark in 2021.

200 Madison Avenue occupies the eastern half of a city block in the Midtown Manhattan neighborhood of New York City, bounded by 35th Street on the south, Madison Avenue on the east, and 36th Street on the north; the city block extends westward to Fifth Avenue. The building's land lot has a total area of 40,981 sq ft (3,807.3 m²); it measures 197.5 ft (60.2 m) from north to south and 220 ft (67 m) from west to east. The building occupies nearly its entire lot, with a frontage of 194 ft (59 m) on Madison Avenue, 196 ft (60 m) on 35th Street, and 220 feet on 36th Street.

200 Madison Avenue is close to the B. Altman and Company Building to the south, the Collectors Club of New York to the southeast, the Church of the Incarnation to the east, and the Morgan Library & Museum. In addition, the Gorham Building at 390 Fifth Avenue, the Tiffany and Company Building at 401 Fifth Avenue, and the Stewart & Company Building at 404 Fifth Avenue are each less than a block away to the west.

The building was designed by Warren and Wetmore. It is 25 stories tall, measuring 374 ft (114 m) to its roof and 385 ft (117 m) to its pinnacle.

The exterior of the building contains a granite water table. Above that, the first story is clad with limestone. On both 35th and 36th Streets, the entrances are within recessed openings and contain five brass doors each. The 35th Street entrance is also topped by a transom window. The lowest nine stories occupy the entire site.

The upper stories contain a facade of red brick with limestone trim. The Madison Avenue elevation of the facade is made almost entirely of brick, except at several places where there is limestone trim. On the 35th and 36th Street elevations, only the outermost bays of windows are made of brick. The remaining bays are separated horizontally by brick piers; within each bay, the windows on different floors are separated horizontally by black spandrels. The spandrels on the second and third stories are made of ornamental ironwork, splitting each bay into multi-part windows. The spandrels on higher stories are made of dull black terracotta and divide each bay into three windows. Robert A. M. Stern and the co-authors of his book New York 1930 wrote that the facades "hardly resulted in the 'Masterpiece of Modern Architecture' claimed by the Real Estate Record and Guide, but they responded sensitively to the residential scale and character of the Murray Hill district".