| Wally Mattick | |
| Position: | Center fielder |
| Birth Date: | 12 March 1887 |
| Birth Place: | St. Louis, Missouri |
| Death Place: | Los Altos, California |
| Bats: | Right |
| Throws: | Right |
| Debutleague: | MLB |
| Debutdate: | April 11 |
| Debutteam: | Chicago White Sox |
| Finalleague: | MLB |
| Finaldate: | July 21 |
| Finalteam: | St. Louis Cardinals |
| Statleague: | MLB |
| Stat1label: | Batting average |
| Stat1value: | .227 |
| Teams: |
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Walter Joseph Mattick (March 12, 1887 – November 5, 1968) was a Major League Baseball center fielder who played for the Chicago White Sox from - and briefly for the St. Louis Cardinals in . He batted and threw right-handed.
Mattick's son Bobby Mattick played 5 seasons in the 1930s and 1940s, mostly with the Chicago Cubs.