The Fresh Kills Landfill was a landfill covering 2,200 acres (890 ha) in the borough of Staten Island in New York City, United States. The name comes from the landfill's location along the banks of the Fresh Kills estuary in western Staten Island.

The landfill opened in 1948, intended to be temporary, but by 1955 had become the largest in the world, and it remained so until its closure in 2001. At the peak of its operation, in 1986, Fresh Kills received 29,000 short tons (26,000 t) of residential waste per day, playing a key part in the New York City waste management system. From 1991 until its closing, it was the only landfill to accept New York City's residential waste. It consists of four mounds that range in height from 90 to about 225 feet (30 to about 70 m) and hold about 150 million short tons (140×10^⁶ t) of solid waste. The archaeologist Martin Jones characterizes it as "among the largest man-made structures in the history of the world."

In October 2008, reclamation of the site began for a multi-phase, 30-year site redevelopment. The landfill has been developed into Freshkills Park.

New York's municipal incinerators peaked in capacity with 21 plants in 1937 and declined during World War II when salvage and conservation programs reduced the use and discard of combustible materials. The result was the closing of nine of the city's incinerators and a sharp reduction in the combustion of waste by 1944. By 1946, only ten incinerators were in operation, with capacity having declined by half since 1937. This meant more solid waste for the city's eight landfills to handle. The two landfills in Brooklyn and the two in the Bronx had, respectively, just one and two years left before reaching capacity. Only one landfill, Edgemere Landfill in Queens, had a long-term future, and as such, an alternative site had to be found.

In 1946, New York City purchased a 2,200-acre (890 ha) site, which was considered worthless swampland in what was then a rural agricultural area in Staten Island, for a proposed three-year municipal waste dump, as a temporary solution to the closing of the Rikers Island Landfill. The plan was endorsed by the Triborough Bridge and Tunnel Authority chairman, Robert Moses. He wanted the area to be developed as Staten Island's industrial base, as it was opposite the Arthur Kill from the heavy industry of New Jersey. Moses saw the project as key to the development of the island, and with it, the possibility of more parkland, highways, industry, and possibly even an airport.

Staten Island residents and their representatives opposed the plan. Assemblyman Edmund P. Radigan introduced a secession bill in the Legislature. A bill was passed (later vetoed by the governor) requiring all garbage to be incinerated before dumping. Ellsworth B. Buck, called for the federal government to step in and stop the project. Cornelius Hall, when he was the city's public works commissioner, opposed the project, but when he became the Borough President of Staten Island, he surprised residents by backing the plan, saying: "I am firmly convinced that a limited landfill project can be undertaken at Fresh Kills, a project that would prove of great value to the island through the reclamation of valuable land from now worthless marshland." Hall intended the landfill to be part of a proposed belt highway along Staten Island's west shore, which was approved by Moses in exchange for his support of the landfill. Hall went on to say "I want [landfilling] operations limited to [a] period not to exceed three years ... I am going along with this proposal because I believe ... we are in a position to use this fill to our advantage, for the development of the West Shore of Staten Island, which is essential." The talk of using Fresh Kills for only three years may have been a ploy to allow Hall to save face politically. As described in an inter-departmental report from 1946: "Because of the substantial sums involved in the preparation and acquisition of the [Fresh Kills] site, [in order to justify this expense] the City must dispose of refuse at this location for a number of years."

One of the first steps taken was the dredging of the marsh to allow the passage of the city's garbage scows. The landfill accepted its first scow in April 1948. Shortly before the landfill opened, an expansion of the landfill project was approved by the City Planning Commission, which called for a 2,200-acre (890 ha) project organized in 13 sections. The landfill was planned to be structured in layers, with a layer of garbage covered by a layer of ash (the remains of burnable trash from the city's incinerators), another layer of garbage, and then a layer of dirt to contain the smell. At the end of the landfill's usable life, new real estate would be created, allowing it to top off at 10–15 feet (3–5 m) above sea level. The plan called for Fresh Kills to be used for 20 years, then developed as a multiuse area with residential, recreational, and industrial components. In 1950, the height was increased to 25–40 feet (8–12 m). By 1955, Fresh Kills was the largest landfill in the world, serving as the principal landfill for household garbage collected in New York City.

Operations during the 1960s were conducted in three locations named "Plant 1", "Plant 2", and "Brookfield Avenue." Plant #1 was located at the site of an old factory on the south side of the junction of the Great Fresh Kills, and Little Fresh Kills. It was reachable via Muldoon Avenue. Plant #2 was located a bit upstream on the north side of Fresh Kills near where Richmond Creek branches off. It was reachable from Victory Boulevard. The Brookfield Avenue site was north of the Arthur Kill Road and Brookfield Avenue intersection.