The Heartbreakers (also credited as Johnny Thunders and the Heartbreakers) were an American punk rock band formed in New York City in 1975. The band spearheaded the first wave of punk rock.

Johnny Thunders (vocals/guitar) and Jerry Nolan (drums) gained fame in the pioneering proto-punk band the New York Dolls. By early 1975, the Dolls were disintegrating amid poor record sales and tensions within the band, and Thunders and Nolan quit during a tour of Florida in March 1975. Coincidentally, that same week Richard Hell (vocals/bass) left Television. After returning to New York, Thunders and Nolan invited Hell to join their new band, and Hell agreed. As Hell said, "I was fed up with Television because it was getting so pretentious...so I thought, this is perfect – we'll make a really good rock & roll band that's dealing with interesting subjects." The three dubbed their new band the Heartbreakers. Their first gig was on May 30 of that year, at the Coventry, a rock club in Queens. (Tom Petty's band was also named the Heartbreakers, but they did not begin gigging until 1976.) The trio auditioned several candidates for a second guitarist, and soon added Walter Lure to the lineup. Lure, who had up to that point been the guitarist for the New York glam punk outfit The Demons, played his first show with the Heartbreakers on July 4, 1975, at CBGB.

The band quickly became one of the most popular and well-known underground bands in New York City, headlining shows at CBGB, Mother's (located across from the Chelsea Hotel), and Max's Kansas City. In the band's early days, each member took turns on vocals, with Hell bringing in songs (such as "Blank Generation") originally written for Television, and Thunders contributing new material as well. Lure began singing lead on some songs and co-writing with Nolan. The combination of the style-conscious Nolan and Thunders with the beatnik Hell and gangly Lure made for a visually arresting and musically powerful group. As Blondie's Clem Burke said, "You could call them the punk rock Beatles. Each person really stood out." Although popular, the early lineup could not get a recording contract, in no small part due to the band's well-known heroin use – as vividly described in their best-known song, "Chinese Rocks" (which was actually written by Dee Dee Ramone with contributions from Hell). Live recordings of the Thunders/Hell/Nolan/Lure lineup were eventually released on the LP Live at Mother's, and studio demos were released in 2019.

Although initially the band members shared songwriting and singing, Hell increasingly attempted to impose his will on the band. At a rehearsal in early 1976, Hell laid down an ultimatum – he would sing most of the songs in the set, with Thunders relegated to one or two songs per set. Thunders walked out, and Nolan and Lure followed; with all three united against him, Hell wound up leaving the band. His final show was on May 14, 1976, at the Rathskeller in Boston. After auditioning several bass players, the band settled on Boston transplant Billy Rath. Hell went on to form his own band, Richard Hell and the Voidoids.

Replacing Hell with Rath solidified the Heartbreakers sound, firmly rooted in 1950s rock and rhythm 'n' blues, but with the energy, volume, and attitude of punk. Rath was a better bassist than Hell, meshing with Nolan to form a formidable rhythm section, and was also content with playing a supporting role in the band without seeking the spotlight. Now managed by Leee Black Childers, the band also consciously emphasized their New York street-tough image, abandoning the glam rock look Thunders and Nolan had flaunted in the New York Dolls in favor of short hair and '50s style suits. The first gigs with the new lineup took place on July 23 and 24, 1976 at Max's Kansas City and earned rave reviews. The band continued to gig regularly in New York City throughout the summer and fall, and played several shows in Boston in September. Despite Childers' efforts and a reputation as a must-see live act, no recording contract was forthcoming, a situation that became increasingly frustrating. Lure wrote that "the kind of deals being offered were laughable, sleazy 50-50 splits that the bands could never, ever hope to profit from." Although the band regularly drew packed crowds at Max's and other venues, by this point Thunders, Nolan, and Lure were heroin addicts (Rath preferred methamphetamine), so money was tight.

The band got what seemed like a break when the Sex Pistols invited the band to open for them on the ill-fated Anarchy Tour (the Sex Pistols at this time were managed by Malcolm McLaren, who had previously managed The New York Dolls). Arriving for the tour just as the UK punk scene was building momentum, the Heartbreakers quickly developed a following in and around London despite most of the shows on the tour being canceled. As Childers said, "The Heartbreakers blew everyone away, for no more reason than they were just more experienced – they had their roots in rhythm and blues and rock 'n' roll...no matter how anarchic an audience thinks it is, if the bass player can actually play, and the drummer is Jerry Nolan, suddenly they're going 'this is GREAT'!" At Childers' behest, the band stayed in London after the conclusion of the tour in order to play more gigs and earn a recording contract. Sold-out gigs at London clubs Dingwalls and the Roxy established the band as one of the top groups in the nascent punk scene, and eventually they signed a contract with Track Records in the spring of 1977, earning a substantial advance and beginning work on their debut album.

By this point, the band members' addictions were out of control, despite being enrolled in the British methadone program. Nolan later acknowledged that "everything we did revolved around drugs." Recording sessions for the new album were derailed by drug use – on the part of band members as well as producer Speedy Keen – leading to innumerable attempts at recording and mixing at different studios. The first release from the sessions was the single "Chinese Rocks" b/w "Born To Lose", released in May 1977, which sold well despite being criticized for its poor sound. Nolan admitted "I think it's okay, but not great," and Lure added "The record wasn't really up to par production wise." Band members continued to attempt to remix the album at various studios in London throughout the summer of 1977, but the problems persisted. In the studio, the band could not seem to capture the power of their live shows – the recordings sounded muddy and lifeless, especially Nolan's drums.

As a live act, at this point the Heartbreakers were second to none – a summer tour of the UK was very successful, with a New Musical Express review describing one gig as "the nearest thing I ever saw to Beatlemania." In August, the band returned to New York City to play three nights at the Village Gate, their first shows in their hometown in nearly a year. Recalled Lure, "It was probably the best shows we ever played in New York, only because we were so tight from touring for six months." These now-legendary shows – which one observer called some of the best rock shows ever – were eventually released as a live album in 2015.