LOS ANGELES — Bob Weir, the illustrious guitarist and singer who co-founded the legendary band Grateful Dead, has passed away at the age of 78.

The news of Weir’s passing was shared on Saturday through an announcement on his Instagram page.

“It is with profound sadness that we share the passing of Bobby Weir,” the statement read. “He transitioned peacefully, surrounded by loved ones, after courageously beating cancer as only Bobby could. Unfortunately, he succumbed to underlying lung issues.”

Weir’s journey with the Grateful Dead began in 1965 when he joined the band at just 17 years old. Originally called the Warlocks, the group quickly became a cornerstone of San Francisco’s vibrant music scene. For the next three decades, Weir was a fixture on stage, performing alongside Jerry Garcia, the band’s iconic singer and guitarist, until Garcia’s death in 1995.

Throughout his time with the Grateful Dead, Weir was instrumental in creating some of the band’s most beloved songs. He either wrote or co-wrote and sang lead on classics such as “Sugar Magnolia,” “One More Saturday Night,” and “Mexicali Blues.”

In the decades since he kept playing with other projects including Dead and Company.

“For over sixty years, Bobby took to the road,” the Instagram statement said. A guitarist, vocalist, storyteller, and founding member of the Grateful Dead. Bobby will forever be a guiding force whose unique artistry reshaped American music.”

Weir’s death leaves drummer Bill Kreutzmann as the only surviving original member. Founding bassist Phil Lesh died in 2024.

Dead and Company played a series of concert’s for the Grateful Dead’s 60th anniversary in July at Golden Gate Park in San Francisco.