Major Leaguers known to have died during the 1904 calendar year.
| Harry Arundel | 1855-02-08 | 1904-03-25 | 49.046 | P | 5-6 | 145 | | R | 1855-02-08 | Philadelphia,PA | MLB | 1875-1884 | 1875-1884 | |
| Henry Austin | 0000-00-00 | 1904-11-02 | | OF | | 0 | | | | | MLB | 1873-1873 | 1873-1873 | |
| Bobby Cargo | 0000-00-00 | 1904-04-27 | | SS | | 0 | R | R | | Pittsburgh,PA | MLB | 1892-1892 | 1892-1892 | |
| Fred Carroll | 1864-07-02 | 1904-11-07 | 40.128 | C-OF | 5-11 | 185 | R | R | 1864-07-02 | Sacramento,CA | MLB | 1884-1891 | 1884-1891 | |
| John Clapp | 1851-07-15 | 1904-12-18 | 53.156 | C-OF | 5-7 | 194 | R | R | 1851-07-15 | Ithaca,NY | MLB | 1872-1883 | 1872-1883 | |
| Dell Darling | 1861-12-21 | 1904-11-20 | 42.335 | C | 5-8 | 170 | R | R | 1861-12-21 | Erie,PA | MLB | 1883-1891 | 1883-1891 | |
| Charlie Dewald | 1867-09-22 | 1904-08-22 | 36.335 | P | | 0 | | L | 1867-09-22 | Newark,NJ | MLB | 1890-1890 | 1890-1890 | |
| Sam Field | 1848-10-12 | 1904-10-28 | 56.016 | C | 5-9 | 182 | R | R | 1848-10-12 | Philadelphia,PA | MLB | 1875-1876 | 1875-1876 | |
| Shorty Fuller | 1867-10-10 | 1904-04-11 | 36.184 | SS | 5-6 | 157 | R | R | 1867-10-10 | Cincinnati,OH | MLB | 1888-1896 | 1888-1896 | |
| John Galvin | 0000-00-00 | 1904-04-20 | | 2B | 5-7 | 178 | | | | | MLB | 1872-1872 | 1872-1872 | |
| Marvin Hawley | 0000-00-00 | 1904-04-28 | | P | | 0 | | | | Painesville,OH | MLB | 1894-1894 | 1894-1894 | |
| John Hayes | 0000-00-00 | 1904-05-25 | | OF | 5-7 | 170 | | | | New York,NY | MLB | 1876-1876 | 1876-1876 | |
| Dan Mahoney | 1864-03-20 | 1904-01-31 | 39.317 | C | 5-9 | 165 | R | R | 1864-03-20 | Springfield,MA | MLB | 1892-1895 | 1892-1895 | |
| Ernie Mason | 0000-00-00 | 1904-07-24 | | P | 6-0 | 150 | | R | | New Orleans,LA | MLB | 1894-1894 | 1894-1894 | |
| Art McCoy | 0000-00-00 | 1904-03-22 | | 2B | | 168 | | | | Danville,PA | MLB | 1889-1889 | 1889-1889 | |
| Chippy McGarr | 1863-05-10 | 1904-06-06 | 41.027 | IF | 5-9 | 168 | R | R | 1863-05-10 | Worcester,MA | MLB | 1884-1896 | 1884-1896 | |
| Gus McGinnis | 0000-00-00 | 1904-04-20 | | P | 5-11 | 168 | | L | | Painesville,OH | MLB | 1893-1893 | 1893-1893 | |
| Gene Moriarity | 1863-01-06 | 1904-05-18 | 41.133 | OF | 5-8 | 130 | L | L | 1863-01-06 | Holyoke,MA | MLB | 1884-1892 | 1884-1892 | |
| Bob Murphy | 1866-12-26 | 1904-12-13 | 37.353 | P | 6-0 | 173 | | | 1866-12-26 | Staten Island,NY | MLB | 1890-1890 | 1890-1890 | |
| Bill Pfann | 0000-00-00 | 1904-06-03 | | P | 6-0 | 205 | | R | | Hamilton,ON | MLB | 1894-1894 | 1894-1894 | |
| Frank Quinlan | 1869-03-09 | 1904-05-04 | 35.056 | C | 5-9 | 180 | | | 1869-03-09 | Marlborough,MA | MLB | 1891-1891 | 1891-1891 | |
| Marshall Quinton | 0000-00-00 | 1904-06-19 | | C | 5-11 | 190 | | | | | MLB | 1884-1885 | 1884-1885 | |
| George Radbourn | 1856-04-08 | 1904-01-01 | 47.268 | P | | 160 | | | 1856-04-08 | Bloomington,IL | MLB | 1883-1883 | 1883-1883 | |
| Charlie Reilley | 0000-00-00 | 1904-11-04 | | C-OF | 5-10 | 165 | R | R | | Providence,RI | MLB | 1879-1884 | 1879-1884 | |
| George Seward | 0000-00-00 | 1904-03-28 | | OF | 5-7 | 145 | | | | New York,NY | MLB | 1875-1882 | 1875-1882 | |
| Jim Shandley | 0000-00-00 | 1904-11-04 | | OF | | 0 | | | | | MLB | 1876-1876 | 1876-1876 | |
| Mike Slattery | 1866-11-26 | 1904-10-16 | 37.325 | OF | 6-2 | 210 | L | L | 1866-11-26 | Boston,MA | MLB | 1884-1891 | 1884-1891 | |
| Charlie Ziegler | 1875-01-13 | 1904-04-18 | 29.096 | IF | | 0 | | R | 1875-01-13 | Canton,OH | MLB | 1899-1900 | 1899-1900 | |
| 28 record(s) |