James, Jim or Jimmy Weir may refer to:

• James Weir (footballer) (born 1995), English football player who last played for ViOn Zlaté Moravce
• Jerry Weir (1851–1889), Scottish footballer (Queen's Park and Scotland)
• Jim Weir (born 1969), Scottish footballer (Hamilton Academical, Heart of Midlothian, St. Johnstone)
• Jim Weir (basketball), American college basketball player
• Jimmy Weir (footballer, born 1864) (1864–?), Scottish footballer (Dumbarton, Gateshead, Sunderland Albion)
• Jimmy Weir (footballer, born 1887) (1887–1959), Scottish footballer (Celtic, Middlesbrough)
• Jimmy Weir (footballer, born 1939), Scottish footballer (Fulham, York City, Mansfield Town, Luton Town, Tranmere Rovers)

• James Weir (politician) (1863–1949), Canadian politician, Alberta MLA (1917–1921)
• James Galloway Weir (1839–1911), Scottish businessman and Liberal Party politician
• Jim Weir (diplomat) (1922–2012), New Zealand diplomat

• James Weir (architect) (1845–1905), Wesleyan Methodist church architect
• James George Weir (1887–1973), Scottish aviator
• James Kenneth Weir (1905–1975), Scottish peer and businessman
• James Robert Weir (1882–1943), American botanist
• Jim Weir (director), Australian writer-director of the 2023 horror film Birdeater

• James Weir Building, an academic building in Glasgow, Scotland
• James Weir House, an historic building in Tazewell, Tennessee