The type is most remembered for its settings of multiple world speed records during the mid-1920s, as well as for winning the Schneider Trophy, for which the M.39 had been specifically developed.

Designed by Mario Castoldi and constructed in Varese, north-western Lombardy, the M.39 was a considerable departure from the company's preceding racing flying boat, the Macchi M.33.

On 13 November 1926, three M.39s participated in the 1926 Schneider Trophy contest, held at Hampton Roads, Virginia, in the United States; one aircraft, MM.76, piloted by Mario de Bernardi, took first place with an average speed of 396.698 kilometres per hour (246.497 mph), setting a new world speed record for seaplanes, while MM.74, flown by Adriano Bacula, came in third place.

The M.39 was designed by the Italian aeronautical engineer Mario Castoldi to represent Italy in the 1926 Schneider Trophy competition.

The oil radiator was incorporated in the bottom of the fuselage in a relatively exposed position to achieve effective cooling.

[6] The power-to-weight ratio achieved by this engine, inclusive of the water in the cylinder jackets and tubing, the residual oil, the starter apparatus and the fuel pump, was exceptionally low (467 grams (1.03 lb.)

[7] The M.39 was specifically built to compete for the Schneider Trophy; accordingly, its design had specialised features to aid it in this exact purpose.

[2] On 13 November 1926, the three M.39 racers took part in the 1926 Schneider Trophy contest at Hampton Roads, Virginia, in the United States.

[2] MM76, the aircraft flown by de Bernadi to win the Schneider Trophy and set a new world speed record, is on display in the Museo Storico Aeronautica Militare in Bracciano.