Sandaime J Soul Brothers (Japanese: 三代目; Sandaime; "Third Generation"), formerly simply J Soul Brothers and also known as Sandaime J Soul Brothers from Exile Tribe, are a J-pop vocal and dance group formed by Exile ex-leader and producer Hiroyuki Igarashi in Japan in 1991. Sandaime J Soul Brothers are managed by Hiroyuki's talent agency LDH and are a part of the supergroup, Exile Tribe. Reformed exclusively by Exile's Vocal Battle Audition in 2010, Sandaime J Soul Brothers released their first single "Best Friend's Girl" in November 2010, which peaked at number three on the Oricon Singles Chart. Their self-titled debut album J Soul Brothers, released in 2011, also peaked at number three. In 2013, they achieved their first number-one record with their third album Miracle.

Sandaime J Soul Brothers were propelled to commercial and critical success following the release of their 2014 single "R.Y.U.S.E.I.", which won the Japan Record Award, the highest honor at the 56th Japan Record Awards. The group's fifth studio album Planet Seven was the second best-selling Japanese album and the third best-selling Asian album of 2015, selling a total of 871,000 physical copies in Japan alone. The album would later attain a Million certification by the RIAJ for having over one million physical copies sold. Additionally, Recochoku revealed the group as the best selling artist of the year with R.Y.U.S.E.I reported as the best selling song for both Recochoku and Billboard year end charts.

By December 2019, Sandaime J Soul Brothers had sold a total of more than 11.15 million records including over 7.25 million singles sales in Japan alone since their debut in late 2010. The group was reported to have earned an estimated total gross of $63.1 million (¥6.85 billion) in 2015 with a total of $76 million (¥8.25 billion) and $53.6 million (¥5.82 billion) earned in the years of 2016 and 2018 respectively.

Hiroyuki Igarashi, who debuted as a member of pop music group Zoo in 1989, first conceptualized the idea of a vocal and dance unit called Japan Soul Brothers in 1991. When ZOO disbanded in 1995, Hiroyuki formed J Soul Brothers, and they released their first self-titled single in 1999. J Soul Brothers halted activities following the departure of their vocalist Sasa in 2001, who wanted to pursue a solo career. The remaining members of J Soul Brothers then changed the group's name to Exile. The reformation into a new group marked the cessation of activities by the original J Soul Brothers before the group would be rebooted for a second generation in 2007.

In January 2007, Exile announced that it would hold an audition to recruit new members for the second generation of J Soul Brothers. Nesmith and Shokichi, finalists of the Exile Vocal Battle Audition, were the first members to join the new generation in August 2007. Performers Kenchi, Keiji, and Tetsuya were soon added. Three months later, performers Naoto and Naoki were added, and they gave their debut performances at Color's 2007 nationwide tour, Live Tour 2007: Blue. The second generation, called the Nidaime J Soul Brothers, released their debut single "We!" in May 2008 under the indies label, Rhythm Republic. Nidaime J Soul Brothers announced their hiatus after the release of their first self-titled album J Soul Brothers in February 2009. A month later, the Nidaime members joined the lineup of Exile. Members Naoto and Naoki stayed behind to re-join J Soul Brothers' third generation.

In July 2010, Japanese music dance group Exile announced on their variety show Shuukan EXILE that the J Soul Brothers would be returning with new members. The new generation, called Sandaime J Soul Brothers, would be led by Exile members Naoto and Naoki Kobayashi, both who were also members of the previous J Soul Brothers lineup. ELLY, a member of the Exile theater group Gekidan EXILE, was announced to be the first new member.

To select a main vocalist for the group, Exile monitored the contestants in the singing competition, Vocal Battle Audition 2. Created by Exile's Hiro in 2006, the Vocal Battle Audition is held every few years to find new talents for their management agency, LDH. Ryuji Imaichi from Kawasaki participated in the first Vocal Battle Audition in 2006, but failed to pass the second screening. Imaichi tried his luck again four years later with the second series of Vocal Battle Audition, auditioning against 30,000 applicants. He finished first place with Hiroomi Tosaka from Tokyo.

In September 2010, Exile confirmed the final new members of Sandaime J Soul Brothers at their concert in Aichi: Gekidan EXILE member Kenjiro Yamashita, new recruit Takanori Iwata, and Vocal Battle Audition 2 winners, Imaichi and Tosaka. Exile then revealed that the new group were in the midst of preparing two debut singles.