The Fiat 500, commonly known as "Topolino",^[4] is an Italian city car produced and manufactured by Fiat from 1936 to 1955.

The name "Topolino" is Italian and translates literally as "little mouse" in English, but is also the Italian name for Mickey Mouse.

The Topolino was one of the smallest cars in the world at the time of its production. Launched in 1936, three models were produced until 1955, all with only minor mechanical and cosmetic changes. It was equipped with a 569 cc four-cylinder, side-valve, water-cooled engine mounted in front of the front axle,^[4] (later an overhead valve motor) and so was a full-scale car rather than a cyclecar. The radiator was located behind the engine which made possible a lowered aerodynamic nose profile at a time when competitors had a flat, nearly vertical grille.^[4] The shape of the car's front allowed exceptional forward visibility.^[5]

Rear suspension initially used quarter-elliptic rear springs, but buyers frequently squeezed four or five people into the nominally two-seater car, and in later models the chassis was extended at the rear to allow for more robust semi-elliptic springs.^[5]

With horsepower of about 13 bhp,^[6] its top speed was about 53 mph (85 km/h), and it could achieve about 39.2 miles per US gallon (6.00 L/100 km; 47.1 mpg‑imp). The target price given when the car was planned was 5,000 lire.^[5] In the event the price at launch was 9,750 lire,^[5] though the decade was one of falling prices in several parts of Europe and later in the 1930s the Topolino was sold for about 8,900 lire. Despite being more expensive than first envisioned, the car was competitively priced.^[5] Nearly 520,000 were sold.

Three models were produced. Model A and B shared the same body, only the engine of model B had 16 hp, vs. 13 hp of Model A. Model A was produced from 1937 to 1948, while B was produced in 1948 and 1949. Model A was offered as a 2-door saloon, 2-door convertible saloon (saloon with folding roof) and a 2-door van,^[1] while Model B also introduced a 3-door estate under the name 500 B Giardinetta ("estate car").

The Giardinetta was at the beginning only available as a so-called woodie, i.e. with an outside ash frame and available in seven metallic colors. When it was later renamed Belvedere, the wood was replaced with metal. This model as well as the regular two-seater Convertible-Limousine were also produced in France by Simca as the Simca 5, and in Germany by the German Fiat subsidiary NSU-Fiat.^[7]

Model C was introduced in 1949 with a restyled body and the same engine as Model B, and was offered in 2-door saloon, 2-door convertible saloon, 3-door estate and 2-door van ^[8] versions. In 1952, Giardinetta was renamed Belvedere ("A turret or other raised structure offering a pleasant view of the surrounding area", referring to its sunroof). Model C was produced until 1955.^[9]

In 1955 the larger rear-wheel-drive Fiat 600 was launched by Fiat and that would become the design basis for the new Fiat 500, the Nuova 500.