e was born in the city of La Plata, capital of the province of Buenos Aires (60 km far from the Federal Capital).
He was the youngest of three children in his family but soon he became an orphan, and so his family moved to Buenos Aires. When he was there he earned his living with different jobs, not suitable for his age.

An acquaintance suggested to him to go to a theater where he got a job as member of a "claque" (hired applauders). One day, because of somebody's idea, they stole some valuable objects placed at a dressing room. There was probably a search, some kind of posse that frightened them because they ran away and finally appeared in the city of Bahía Blanca (600 km far south from Buenos Aires).

There he split with the bad company and began to work at a printing house that published the local paper: "Hoja del Pueblo". His inborn capabilities to write made him become journalist, under the guidance of the director of the periodical, who was his advisor and protector. In this way, he found his vocation.

The great national actor Enrique Muiño, then visiting the city, read an article signed by Caruso and congratulated him, encouraging him to continue with the profession.

In 1910 he returned to Buenos Aires, he settled in the neighborhood of San Cristóbal (south center of the city) and soon became friends with boys of the surroundings. Francisco Canaro, recalls in his memories:
«I met him for the first time between 1910 and 1912. He was a journalist and was admitted in our group: with my brothers, with the Grecos, Bardi, Prudencio Aragón, Castriota, the Tano Genaro, the Tuerto (one-eyed) Camarano and others. He coincided in many aspects with me and we had a great friendship until his death. As lyricist he brought his wit and his grace to my compositions. He wrote his first lyric for me, it was the tango "Carasucia". He also wrote the script for my first attempt in theater: "Nobleza de arrabal". He was a born poet with refined inspiration. The concepts in his lyrics were ahead of his time. He was a tall, elegant, good-looking man.»

He wrote lyrics for different native airs: estilos, milongas camperas and zambas. "Mi noche triste" had not been released yet. As it happened with Luis César Amadori, Manuel Romero and other authors, Caruso as well switched from journalism to theater and tango.

He entered the "La Montaña" newspaper as editor, later he joined the editorial staffs of "Crítica", "Última Hora", "Mundo Argentino" and led a publication specialized in theater called "El Teatro Nacional".

He eventually directed theater, in the popular genre, sainete (one-act farce), which was nurtured by musical numbers that ought to be made for the occasion. For this reason, those who wrote the scripts of the plays were those in charge of creating the lyrics for the musical numbers.

Among his over thirty works for theater, the first, "Nobleza de arrabal", was premiered in 1919 at the Teatro Variedades -a few meters from Constitución station. He also wrote the tango that bears the same title, with music by Francisco Canaro, but the lyric which was popularly known later was not his but the poet Homero Manzi's, who signed it under the pseudonym Arauco.

The researcher Jorge Larroca, when writing about the neighborhood of San Cristóbal, refers to Juan Caruso placing him as an avant-gardist of the picturesque tango; that is to say, the tango that portrays the mocking spirit of the man of Buenos Aires, describing the subtle aspects of his peculiar idiosyncrasy.

In 1921 he married the actress Elvira Quiroga.

Since 1927 he worked as secretary for Enrique Muiño and was manager of the artistic team Muiño-Alippi. Canaro recalls, that because of a premiere Caruso called him requesting that the former should write the music for a lyric the latter had just made: "La última copa". Canaro soon answered and so another big boom of the team was born.

He was the author with most compositions sung and recorded by Gardel, a total of 38. Ignacio Corsini as well regarded him as one of his preferred authors, he committed to record 31 of his pieces.

In the mid- twenties his decline began. He was ill several years and under severe treatment, his activity notably decreased as well as his courage and love for life. He passed away on March 1st, 1931.