| Fiendish Regression | |
| Type: | studio |
| Artist: | Grave |
| Cover: | Fiendish regression.jpg |
| Released: | 23 August 2004 |
| Recorded: | April–May 2004 at Studio Abyss |
| Genre: | Death metal |
| Length: | 50:30 |
| Label: | Century Media |
| Producer: | Peter Tägtgren, Tommy Tägtgren |
| Prev Title: | Back from the Grave |
| Prev Year: | 2002 |
| Next Title: | As Rapture Comes |
| Next Year: | 2006 |
Fiendish Regression is the sixth album by Swedish death metal band Grave. It was released on 23 August 2004 through Century Media Records.