Massimo attended the R. Liceo Ginnasio Giuseppe Parini in Milan, where his literature teacher was Alfredo Panzini, and in 1897 graduated in Alessandria.

Starting from 1904 he published a series of collections of poems and short stories, as well as a tragedy in verse, Costanza, and a comedy, Santa Teresa, all works of a classicist character.

An adherent of Giosuè Carducci in the debates with followers of Benedetto Croce, he published essays in the field of literary criticism as well as a volume of stories Sette Savi.

A convinced interventionist, in 1917 he enlisted as an artillery officer, while also collaborating on the military newspaper Il Montello and obtaining two medals for valour and three war crosses.

It was his time as a journalist in Paris in the years 1921 and 1922 that put him in contact with the new French avant-gardes and profoundly changed his image of the modern artist.

In the short novels The chessboard in front of the mirror (1922) and Eva ultima (1923) he employed a style inspired by the irrational arbitrariness and the apparent randomness of dreams, a writing approach that largely coincides with the pronouncements of the Surrealist Manifesto by André Breton (1924).

Alongside his friends Alberto Savinio and Giorgio de Chirico, he pioneered surrealistic experiments in Italian art, which he defined as magical realism.

The results were Nostra Dea (1925) and Minnie la candida (1927), perhaps Bontempelli's theatrical masterpiece, a fairy-tale drama, albeit plausible, that takes place in an atmosphere that always oscillates between nightmare and play.

On 8 August 1926, in the villa of Pirandello, near Sant'Agnese, he was challenged to a duel by Giuseppe Ungaretti, due to a controversy that arose in the Roman newspaper Il Tevere.

James Joyce, Max Jacob, and Rainer Maria Rilke sat on the editorial committee and Virginia Woolf and Blaise Cendrars were among the contributors.

In March 1927, Bontempelli, who had separated from his wife, began a relationship with Paola Masino, who was thirty years younger.

Masino worked with Bontempelli on "900" and together they wrote the unreleased drama, "The Sinking of the Titanic", then moved with him to Paris, where they encountered artists and intellectuals such as Ilya Ehrenburg, Paul Valéry, Max Jacob, André Maurois, André Gide, Emil Ludwig, Giorgio de Chirico, Alberto Savinio, and Pirandello.

He served as a secretary of the fascist writers' union from 1928 and spent time abroad lecturing on Italian culture.

[5] Prohibited by the authorities from writing for a year, he and Masino left Rome and resided in Venice, in a sort of "golden exile", at the villa of Baron Franchini.

[6] After the fall of Mussolini he returned to Rome, but the death sentence issued by the Republic of Salò, the new regime led by Alessandro Pavolini, forced him and Masino to hide in a friend's house.

In 1948, Bontempelli won a Senate race on the Popular Democratic Front ticket but the results were voided in 1950 when his role editing an anthology of Italian literature for school children, which triggered the provisions barring anyone who had authored school texts from holding public office for five years after adoption of the new Constitution was discovered.

After years of declining health that prevented him from continuing his work, Bontempelli died in Rome at the age of 82 on 21 July 1960.