| Career On-Base Percentage | |||
| Rank | Name | Seasons | OBP |
| 1 | Brian Moran | 2007-08 | .516 |
| 2 | Steve Shilling | 1991-93 | .494 |
| 3 | John Senkowitz | 1984-87 | .488 |
| 4 | Seth Thompson | 2006-09 | .486 |
| 5 | Nate Kauffman | 1998-2001 | .481 |
| 6 | Andy Fritz | 2014-Pres. | .479 |
| 7 | Marcus Magister | 2008-11 | .470 |
| 8 | Reynold Petre | 1965, 67-69 | .468 |
| 9 | Jim Donnelly | 1996-98 | .463 |
| 10 | Greg Pierce | 1975-77 | .458 |
| Single-Season On-Base Percentage | |||
| Rank | Name | Season | OBP |
| 1 | Brian Moran | 2008 | .559 |
| 2 | Eric Kephart | 1997 | .556 |
| 3 | John Avdellas | 1988 | .551 |
| 4 | Josh Sacks | 2010 | .536 |
| 5 | Nate Kauffman | 1998 | .534 |
| 6 | Greg Grupp | 2003 | .533 |
| 7 | John Senkowitz | 1986 | .532 |
| 8 | Mike Ritter | 2003 | .524 |
| 9 | John Senkowitz | 1985 | .522 |
| 10 | Seth Thompson | 2007 | .521 |