Frost made his MLB debut on September 11, 1977, against the California Angels at Anaheim Stadium. He turned in a quality start, pitching 61⁄3 innings and giving up just two earned runs. He struck out three, walked none, and received a no decision in the 5–4 White Sox loss. His first big league win came a week later in another start against the Angels, this time at Comiskey Park. He went 72⁄3 innings, gave up three runs, and won 7–3.

Frost was traded along with Brian Downing and Chris Knapp to the Angels for Bobby Bonds, Richard Dotson, and Thad Bosley on December 5, 1977.^[1] He split time between the Salt Lake City Gulls of the Pacific Coast League and the big leagues in 1978, and went 5–4 with a 2.58 earned run average (ERA) in 11 games (ten starts) for the Angels.

Frost had his biggest year in 1979. He won 16, lost 10, and led Angel starters in ERA (3.57), winning percentage (.615), and innings pitched (2391⁄3). California had an impressive group of starters that year, including Frost, Nolan Ryan, Don Aase, Jim Barr, Chris Knapp, and Frank Tanana. They ultimately won the American League West Division pennant that year with an 88–74 record.

Elbow problems severely limited Frost's effectiveness for the remainder of his career. In the next three seasons (two with the Angels and one with the Kansas City Royals) he was a combined 11–22 with a 5.43 ERA.

Frost's career totals for 99 games pitched include a 33–37 record, 84 games started, 16 complete games, 3 shutouts, 1 save, and 7 games finished. He allowed 251 earned runs in 5502⁄3 innings pitched, giving him a lifetime ERA of 4.10.

His career highlights include a four-hit, no walk complete game shutout vs. the Oakland A's (July 3, 1979), an eight-strikeout, no walk complete game win (10–1) vs. the Baltimore Orioles (July 7, 1979), and a ten-inning, four-hit complete game win (2–1) vs. the Minnesota Twins (April 16, 1980). Over the course of his career, Frost held All-Stars Sal Bando, Buddy Bell, Mike Hargrove, Rickey Henderson, Roy Howell, Pat Kelly, Hal McRae, Willie Randolph, Jim Rice, and Roy Smalley to a .103 collective batting average (15-for-145), and held Hall of Famers Reggie Jackson, Cal Ripken Jr., and Robin Yount to a .167 collective batting average (3-for-18).^{[original research?]}

Frost threw the opening pitch at a Los Angeles Angels game on Monday, June 27, 2011.

Frost died from injuries sustained in a car accident on April 14, 2023, in Kindred Hospital in Westminster, California, at the age of 70.^[2]

• Chicago White Sox all-time roster

• Career statistics and player information from MLB, or ESPN, or Baseball Reference, or Fangraphs, or Baseball Reference (Minors), or Retrosheet
• Dave Frost - Baseball Biography and Highlights