Williams was born on December 9, 1930 in Newton County, Arkansas (or Bullfrog Valley, Pope County, Arkansas), as part of a musical family; family members played fiddle, guitar, and banjo. Williams started on guitar, then switched to mandolin at age 17. In 1952, he was drafted into the Marines and moved to San Diego, California, for basic training. After serving at Twentynine Palms, California, he married and moved to Stockton, California.
In 1960, Williams formed a duo with fiddler Ray Park called Vern and Ray. Vern and Ray became one of the most successful bluegrass bands in the San Francisco regions. According to country show host Tom Diamant, "Anybody who plays bluegrass in the Bay area and sings the tenor part has been influenced by Vern Williams. He was one of the greatest tenor singers in history"
After the breakup of Vern and Ray, Williams formed the Vern Williams Band which included his son, Delbert, on guitar, fiddler Ed Neff and singer and banjoist Keith Little. The band became known as a "powerhouse bluegrass outfit". In 1980, they signed with Rounder Records and, shortly afterwards, recorded Bluegrass from the Gold Country which enjoyed regional successful and is now considered a minor classic. The Vern Williams Band also backed up country-bluegrass legend Rose Maddox in her later years. The band broke up in 1986.
Williams worked with many younger musicians, both in Vern and Ray, and the Vern Williams Band, who went on to successful careers of their own including Jerry Garcia, Herb Pedersen, Laurie Lewis, Peter Wernick, Sandy Rothman, and Rick Shubb. Lewis said of her year with the Vern Williams Band, "I was in heaven, with the best seat in the house for that scraped-clean, unvarnished sound" and "Playing with them ... has always been among the highlights of my musical career."
In 1997, Williams was awarded a Distinguished Achievement Award from the International Bluegrass Music Association's (IBMA), and he was the first to be awarded an Honorary Lifetime Membership in the California Bluegrass Association.