Jula De Palma was born Iolanda Maria Palma in Milan on April 21, 1931. She was discovered by the pianist and bandleader Lelio Luttazzi, who got her a recording contract with CGD, the label Teddy Reno had founded, and she made her radio debut in 1949 at about eighteen. Her first records were French songs on CGD 78s, among them "Douce France" and "Danse avec moi" (1949), and for the first part of her career she leaned on a French repertoire, a language she spoke fluently along with English. In 1950 she recorded "Cheveux dans le vent" and "September Song" with Luttazzi's small group, and over the next few years she sang with his rhythmic string orchestra on the radio.

She also became the featured vocalist of the group led by bassist Carlo Loffredo and of the orchestra of Gorni Kramer, both fixtures of Italian radio. In 1954 she won a Venetian song contest with the group Radio Boys, singing "Marieta monta in gondola". From 1955 to 1961 she took part in the Sanremo festival, and she recorded songs written by Luttazzi and Kramer ("Quando una ragazza (a New Orleans)", "Souvenir d'Italie", "Mia vecchia Broadway"), film themes such as "Que sera, sera", French songs, Neapolitan songs, and American standards including "That Old Black Magic" and "All the Way". In June 1957 she married the composer Carlo Lanzi, who later produced her live album.

The jazz records came at the end of the 1950s. Columbia issued two English-language EPs, In Jazz (1958) and In Jazz N° 2 (1959). The first was recorded with a quartet led by Luttazzi at the piano, with Franco Chiari on vibraphone, Giovanni Alceo Guatelli on bass and Lionello Bionda on drums, and covers "Just One of Those Things", "Blues in the Night", "The Nearness of You" and "Pennies from Heaven". The second pairs her with the trio of guitarist Franco Cerri, with Renato Sellani on piano, Giorgio Azzolini on bass and Gianni Cazzola on drums, for "One for My Baby", "Cheek to Cheek", "Everything Happens to Me" and "I've Got You Under My Skin".

Her best-known record has nothing to do with jazz. "Tua", which she sang with Tonina Torrielli at Sanremo in 1959, finished fourth with the juries and sold well, but RAI officials and parts of the press judged her delivery too sensual, and the record was kept off the air. Italian accounts say she received thousands of angry letters. The episode did not end her career: she returned to Sanremo in 1960 and 1961, and she kept working through Canzonissima, the Naples song festivals and a series of tours abroad that took in Brazil, Egypt and Cuba, singing in several languages.

The 1960s brought two long-players that lean toward jazz. Hello Jula (Surf, 1965) mixed Italian pop with standards such as "I Left My Heart in San Francisco". Whisky e Dixie (Cetra, 1967) is a Dixieland album recorded with Carlo Loffredo's New Orleans-style band: Gianni Sanjust on clarinet, Marcello Rosa on trombone, Piero Saraceni on trumpet, Carlo Sili on tuba, Rodolfo Mattozzi on piano and Antonio Golino on drums, working through "Night and Day", "Mon homme", "Moritat" and "Mister Paganini". In April 1970 she became the first woman to give a solo recital at the Teatro Sistina in Rome, with the orchestra of Gianni Ferrio and soloists she chose herself. RAI broadcast the concert more than once and RCA Italiana issued it as Jula al Sistina (Dal Vivo), a mix of Italian songs (including two associated with Mina) and "St. Louis Blues", "That Old Black Magic", "I Won't Dance" and the bossa nova "Desafinado". Jula presenta (RCA Italiana, 1974) reissued most of that program and added three new tracks with a small group that included Dino Piana on trombone, Livio Cerveglieri on tenor saxophone and clarinet, and Antonello Vannucchi on organ and piano, with arrangements by Ferrio.

Italian sources date her retirement from the stage to between 1972 and 1974. Her last television appearance was the 1974 variety show Milleluci, after which she moved with her family to Toronto, Canada, where Italian sources continue to place her. She came back to public attention from the late 1990s, helped by a renewed interest in jazz, when her long-unavailable records began circulating among collectors. In 2001 she sang a medley on a pair of RAI programs devoted to her career, hosted by Paolo Limiti. Her autobiography, Tua per sempre, subtitled as the life story of the lady of Italian jazz, was published by Coniglio Editore in November 2009. In 2010 she received the honorary career award at the fourth Italian Jazz Awards. Sonorama issued a compilation of her jazz sides, Jula in Jazz, in 2011. She also sings two songs on Speciale per Lelio, a tribute to Luttazzi by the swing group Voci di Corridoio, and in 2015 the digital album Unforgettable Jula finally released ten tracks she had recorded in London in 1972, several with English lyrics by Norman Newell.

De Palma is a pop singer with a jazz side rather than a jazz specialist. Most of her recordings are Italian light song, French chanson, Neapolitan songs and Sanremo entries, and "Tua" remains the title she is known for. What set her apart in the Italy of the early 1950s was her phrasing: she brought a sense of swing and a modern, speech-like delivery to a scene dominated by melodic, ornamented singing, and she sang American standards, which was unusual for the Italian radio repertoire of the time. The jazz repertoire is concentrated in a handful of releases, the two English-language EPs, the Dixieland LP with Loffredo, and the 1970 and 1974 recital records, which blend swing, blues and bossa nova into Italian and French material. Her closest musical relationship was with Lelio Luttazzi, who found her, arranged and conducted for her, and wrote "Eccezionalmente sì" for her. Her official website calls her the lady of Italian jazz, and the Italian Jazz Awards honored her with a career prize in 2010.