MLB Players — U
71 MLB baseball players with last names starting with U.
- Uceta, Edwin 2021–
- Uchrinscko, Jimmy 1926–1926
- Uecker, Bob 1962–1967
- Uehara, Koji 2009–2017
- Uelmen, Erich 2022–
- Uggla, Dan 2006–2015
- Ugueto, Luis 2002–2003
- Uhalt, Frenchy 1934–1934
- Uhl, Bob 1938–1940
- Uhlaender, Ted 1965–1972
- Uhle, George 1919–1936
- Uhler,
- Uhler, Maury 1914–1914
- Uhlir, Charlie 1934–1934
- Ujdur, Jerry 1980–1984
- Ulicny, Mike 1945–1945
- Ullger, Scott 1983–1983
- Ullrich, Sandy 1944–1945
- Ulrich, Frank 1925–1927
- Ulrich, George 1892–1896
- Umbach, Arnold 1964–1966
- Umbarger, Jim 1975–1978
- Umbricht, Jim 1959–1963
- Umphlett, Tom 1953–1955
- Underhill, Vern 1927–1928
- Underwood,
- Underwood, Duane 2018–
- Underwood, Eli
- Underwood, Fred 1894–1894
- Underwood, Pat 1979–1983
- Underwood, Tom 1974–1984
- Unglaub, Bob 1904–1910
- Unroe, Tim 1995–2000
- Unser, Al 1942–1945
- Unser, Del 1968–1982
- Upchurch, Woody 1935–1936
- Upham, Bill 1915–1918
- Upham, John 1967–1968
- Upp, Jerry 1909–1909
- Upright, Dixie 1953–1953
- Upshaw, Cecil 1966–1975
- Upshaw, Willie 1978–1988
- Upton, B. J. 2004–2016
- Upton, Bill 1954–1954
- Upton, Justin 2007–2022
- Upton, Tom 1950–1952
- Urban,
- Urban, Jack 1957–1959
- Urban, Luke 1927–1928
- Urbani, Tom 1993–1996
- Urbanski, Billy 1931–1937
- Urbina, Ugueth 1995–2005
- Urdaneta, Lino 2004–2007
- Urena, Jose 2015–
- Urena, Richard 2017–2019
- Urias, Julio 2016–
- Urias, Luis 2018–
- Urias, Ramon 2020–
- Uribe, Abner 2023–
- Uribe, Jose 1984–1993
- Uribe, Juan 2001–2016
- Urquidy, Jose 2019–
- Urrea, John 1977–1981
- Urrutia, Henry 2013–2015
- Urshela, Gio 2015–
- Urueta, Luis
- Ury, Lon 1903–1903
- Usher, Bob 1946–1957
- Ussat, Dutch 1925–1927
- Utley, Chase 2003–2018
- Uwasawa, Naoyuki 2024–