Before embarking on a singing career, Sebastian was an administrative assistant at a vacation resort in Oaxtepec, Morelos, where he would sing through the intercom. In 1968, Sebastian met Mexican actress Angelica Maria. They stayed together and she asked him to sing some songs for her. She suggested to Sebastian that he record the songs and give them to music producer Eduardo Magallanes, though Sebastian never managed to contact him. He later moved to Mexico City and began asking Discos Capitals Records to listen to his music and produce it. In 1974, he recorded his first album, Pedro Parrandas, and received positive feedback from the public.

In 1977, Sebastian decided to stop using his legal name, Jose Manuel Figueroa and took on his artistic name, Joan Sebastian, partly in tribute to San Sebastian, where he previously worked. That same year, he signed a record deal with the label Musart. Later on he would make his known hit “Juliantla” and the famous duet Maracas with Alberto Vazquéz. In 2000, he released Secreto de Amor which was certified 4× platinum in the Latin field in the United States by the Recording Industry Association of America (RIAA). The album and title track won the Lo Nuestro Awards for Regional Mexican Album of the Year and Regional Mexican Song of the Year; he also received the Excellence Award for his musical contributions.

Sebastian was first diagnosed with bone cancer in 1999. He underwent cancer treatment and survived; however, he announced that the cancer had returned in 2007. Undergoing cancer treatment once again, he later announced he was in remission. On July 26, 2012, during one of his concerts, he announced that the cancer had returned for the third time. In 2014, he revealed that he was battling cancer for the fourth time during his performances in Zacatecas.

In 2006, Sebastian was inducted into the Billboard Latin Music Hall of Fame for his prolific songwriting and musical arrangements. Sebastian was awarded Songwriter of the Year three times by ASCAP and received the Golden Note Award in 2007 in recognition of his songwriting career.

Sebastian had eight children from five different women. Their names are José Manuel Figueroa (who is also a singer and composer), Juan Sebastián Figueroa González, Trigo de Jesús Figueroa González (first three children with Teresa González, his first wife), Zarelea Figueroa Ocampo (who is also a singer and composer), Marcos Julián Figueroa Fernández (son of Maribel Guardia, who’s a singer and has a son with Imelda Tuñon), Joana Marcelia Figueroa Espín, Juliana Joeri Figueroa Alonso and D’Yave Figueroa Espín. His third oldest son, Trigo was shot in the back of the head after one of Joan Sebastian’s concerts in Mission, Texas on August 27, 2006. Trigo had been trying to control the crowd after the show. He was transported to McAllen Medical Center where he was pronounced dead.

On June 12, 2010, his second oldest son, Juan Sebastián was shot dead in Cuernavaca, Morelos, after arriving at a night club with some friends and being refused entrance. Joan Sebastian said his son’s death had nothing to do with the Mexican drug cartels.

In 2012, Joan Sebastian teamed up with American songwriter and producer Will.i.am for the song and video “Hey You.”

Weeks prior to his death, he confirmed to the media that he had been hospitalized and undergoing cancer treatment under medical supervision. On July 13, 2015, Joan Sebastian died at 7:15pm (UTC-06:00) at his ranch Cruz de la Sierra, Teacalco Guerrero, Mexico, due to bone cancer. He was 64 years old. His body was buried in a cemetery in Juliantla near his son Trigo.

A few months after his death Televisa announced that a series about his life would begin filming. His youngest son, Julian Figueroa, portrayed his father in his younger days while his older son, José Manuel Figueroa, portrayed his father in his later days. Livia Brito was also confirmed to portray Maribel Guardia. The series Por Siempre Joan Sebastian premiered on June 27, 2016 on Univision and concluded on July 25, 2016.

On January 27, 2019, a nephew-in-law of Sebastian, Hugo Figueroa, was kidnapped before the start of a bull riding event in Tarímbaro, Michoacán. On January 31, he was found dead with multiple gunshot wounds, at kilometer 294 of the Mexico-Guadalajara highway. This marked the third violent death in the famous Mexican family. A video allegedly depicting his murder has circulated online. Figueroa was buried not far from his uncle’s grave.

Relatives of the late singer complained in July 2020 that Sebastian’s mausoleum had been broken into and the family feared that his bones might be stolen. Security measures were increased.