| 1999 SEAT Open Luxembourg | |
|---|---|
| Date | 20–26 September |
| Edition | 4th |
| Category | Tier III |
| Draw | 30S / 16D |
| Prize money | $180,000 |
| Surface | Carpet / indoor |
| Venue | Kockelscheuer, Luxembourg |
| Champions | |
| Singles | |
 Kim Clijsters | |
| Doubles | |
 Irina Spîrlea /  Caroline Vis | |
The 1999 SEAT Open was a women's tennis tournament played on indoor carpet courts in Kockelscheuer, Luxembourg which was part of Tier III of the 1999 WTA Tour. It was the fourth edition of the tournament and was held from 20 September until 26 September 1999. Qualifier Kim Clijsters won the singles title and earned $27,000 first-prize money.
