The 1921 College Baseball All-Southern Team consists of baseball players selected at their respective positions after the 1921 NCAA baseball season. Vanderbilt won the SIAA.
| Position | Name | School | Notes | |
| Pitcher | Jack Frost | Georgia | ||
| Pitcher | Cliff Pantone | Georgia | CW | |
| Pitcher | Tige Stone | Mercer | CW | |
| Pitcher | Chief Turk | Oglethorpe | CW | |
| Pitcher | Sunshine Thompson | Georgia Tech | CW | |
| Pitcher | Ollinger | Auburn | ||
| Pitcher | George Johnson | Auburn | CW | |
| Pitcher | Jim Joe Edwards | Mississippi College | CW | |
| Catcher | Charlie Gibson | Auburn | ||
| Catcher | Byrd Hope | Oglethorpe | CW | |
| Catcher | Luke Sewell | Alabama | CW | |
| First baseman | Lassiter | Auburn | ||
| First baseman | Chief Cody | Georgia | CW | |
| First baseman | Bevo Webb | Georgia Tech | ||
| Second baseman | Sam Barnes | Auburn | CW | |
| Third baseman | Eddie Morgan | Georgia Tech | CW | |
| Shortstop | Dot Fulghum | Auburn | CW | |
| Shortstop | Doc Kuhn | Vanderbilt | ||
| Outfielder | Esau Settle | Georgia Tech | CW | |
| Outfielder | Red Barron | Georgia Tech | ||
| Outfielder | Sox Ingram | Georgia Tech | ||
| Outfielder | Roy Carlysle | Oglethorpe | ||
| Outfielder | Ed Sherling | Auburn | ||
| Outfielder | Manning Brown | Vanderbilt | ||
| Outfielder | Boozer McWhorter | Georgia | ||
| Outfielder | Country Mangum | Georgia | CW | |
| Outfielder | Tot McCullough | Vanderbilt | CW |
CW = Cliff Wheatley's selection.[2]