Thomas Casey may refer to:

• Thomas Casey (Kilmallock MP) (1765–1840), Irish politician
• Thomas Lincoln Casey Sr. (1831–1896), United States Army Corps of Engineers
• Thomas Lincoln Casey Jr. (1857–1925), American expert in coleoptera and son of Thomas Lincoln Casey Sr.
• Thomas S. Casey (1832–1891), American judge and politician
• Thomas Worrall Casey (1869–1949), British Liberal Member of Parliament
• Tommy Casey (baseball), 19th-century American baseball pitcher
• Tom Casey (Australian politician) (1921–2003), South Australian MHA and MLC
• Tom Casey (Canadian football) (1924–2002), Canadian football player for Winnipeg Blue Bombers
• Tommy Casey (1930–2009), Northern Irish footballer
• Tom Casey (diplomat), American diplomat