Dennis Bryan Cook (born October 4, 1962) is an American former professional baseball pitcher who played in Major League Baseball (MLB) with the San Francisco Giants (1988–1989), Philadelphia Phillies (1989–1990, 2001), Los Angeles Dodgers (1990–1991), Cleveland Indians (1992–1993, 1995), Chicago White Sox (1994), Texas Rangers (1995–1996), Florida Marlins (1997), New York Mets (1998–2001), and Anaheim Angels (2002). He made his big league debut on September 12, 1988, and played his final game on September 18, 2002.

Cook graduated from Dickinson High School in 1981. In college Cook was named to the All-Southwest Conference Team as an outfielder at the University of Texas in both 1984 and 1985.

Cook was a member of the 1997 World Champion Marlins, pitching in the World Series and was the winning pitcher in relief in Game 3.

Although not on the postseason roster, Cook was a member of the 2002 Angels team that won the World Series, defeating the Giants.

Although a pitcher, Cook was also a good hitter and he is number 2 on the list of Major League All-Time Best Hitting Pitchers between 1973 and 2003 (with 100 or more at-bats). His batting average was .264 (29-for-110) and he had two career home runs.

On February 1, 2010, Cook was announced as the Team Sweden's new head coach along with Scott Scudder in the coaching staff.^[1]

In 2018, Cook became the pitching coach for the Chatham Anglers of the Cape Cod Baseball League.^[2]

Cook was named manager of the Poland national baseball team in April 2024.^[3]