Cavalera started playing drums around 7 years old. He was into samba music as a child but, after watching Queen live in 1981 along with his brother Max, he started listening to rock music. When Sepultura was formed, Cavalera was the youngest member at the age of 13, his brother Max was 14 at the time. Sepultura was a big success and gave Cavalera an early start. On April 21, 1984, Cavalera played, for the first time, on a real drum kit, which was borrowed from Helinho of the band Overdose, that also played that night.

After the band split with his brother Max (lead vocals/rhythm guitar) in 1996, their relationship underwent a crisis. In recent times their relationship has improved. Cavalera joined Max’s current band Soulfly on stage at the 2006 tenth annual D-Low Memorial Show, to play the Sepultura songs “Roots Bloody Roots” and “Attitude”. It was the first time the brothers had played together in ten years.

Cavalera collects toys and football shirts and has many hobbies, including Brazilian jiu-jitsu, snowboarding, surfing, drawing and supporting Brazilian football club Palmeiras. He admires his father Graziano Cavalera as his role model. He has four children: Christian Bass Cavalera (b. November 7, 1996), Raissa Bass Cavalera (b. April 26, 2000), Iccaro Bass Cavalera (b. November 23, 2002), Antonio Leyton Cavalera (b. January 15, 2006) (the first with his current wife Laima Leyton) and a stepson Pedro Leyton Pereira. In 1996 he started the fashion label “Cavalera”. His fashion label has faced controversy of its use of the Albanian flag as its logo. In 2020, a petition called for “Cavalera” to change it. He lives in London since 2013.

In the early Sepultura albums his drumming was loud and fast, following the thrash metal style of the 80s. He mastered this style by 1987–1991 (with Schizophrenia, Beneath the Remains and Arise). His innovative style in the album Chaos A.D. brought tribal elements into the songs. One example of his contribution is the introduction of the song “Territory” (1993, Chaos A.D.). He further developed this style in the 1996 Roots album, adding more tribal elements to Sepultura’s music.

He is credited as having made a guest appearance on Biohazard’s 2001 release Uncivilization on the track “Gone”.

In 2006, with the release of Dante XXI, he began spelling his name “Iggor,” preferring the way it looks. On January 13, 2006, it was announced that he was taking a break from the band due to the birth of his fourth child, initially leaving Sepultura temporarily. He later announced that he was quitting Sepultura due to “artistic incompatibility.” Sepultura replaced him with Jean Dolabella.

Cavalera was scheduled to collaborate with underground hip hop artist Necro, on a project described by Necro as in the style of “old-school ’80s thrash/death metal.” However, Necro mentioned later that the project will not go ahead. In 2008 he released the album Inflikted together with his brother Max in a project named Cavalera Conspiracy.

In 2012, Cavalera performed drums for the entire Strife album Witness A Rebirth, released via 6131 Records.

In 2017, Cavalera performed drums for Soulwax on their album “From Deewee” and in their live tour, along with two other live drummers.

In 2018, Cavalera formed the Noise music duo PET BRICK with Wayne Adams of Big Lad and Death Pedals