| Doubles | |
|---|---|
| 1998 Sybase Open | |
| Champions |  Mark Woodforde Todd Woodbridge |
| Runners-up |  Nelson Aerts André Sá |
| Score | 6–1, 7–5 |
| Draw | 16 |
| Seeds | 4 |
The 1998 Sybase Open was a men's tennis tournament played on indoor hard courts at the San Jose Arena in San Jose, California in the United States and was part of the ATP World Series of the 1998 ATP Tour. It was the 109th edition of the tournament ran from February 9 through February 15, 1998.
Champion seeds are indicated in bold text while text in italics indicates the round in which those seeds were eliminated.
Todd Woodbridge / Mark Woodforde (champions) Gustavo Kuerten / Fernando Meligeni (first round) David Macpherson / 
Richey Reneberg (quarterfinals)
Wayne Black / Jeff Salzenstein (semifinals)| First round | Quarterfinals | Semifinals | Final [1] | ||||||||||||||||||||||||
| 1 | T Woodbridge M Woodforde | 6 | 6 | ||||||||||||||||||||||||
B Coupe  P Rosner | 3 | 4 | 1 | T Woodbridge M Woodforde | 6 | 7 | |||||||||||||||||||||
| G Stafford J Waite | 1 | 6 | 7 | G Stafford J Waite | 4 | 5 | |||||||||||||||||||||
 S Sargsian G Van Emburgh | 6 | 4 | 6 | 1 | T Woodbridge M Woodforde | 7 | 7 | ||||||||||||||||||||
| 4 | W Black J Salzenstein | 6 | 6 | 4 | W Black J Salzenstein | 5 | 6 | ||||||||||||||||||||
| J Palmer J Stark | 3 | 4 | 4 | W Black J Salzenstein | W/O | ||||||||||||||||||||||
| J Gimelstob B MacPhie | 6 | 7 | J Gimelstob B MacPhie | ||||||||||||||||||||||||
 T Haas M Philippoussis | 2 | 6 | 1 | T Woodbridge M Woodforde | 6 | 7 | |||||||||||||||||||||
| N Aerts A Sá | 6 | 6 | 6 | N Aerts A Sá | 1 | 5 | |||||||||||||||||||||
| B Bryan M Bryan | 7 | 3 | 4 | N Aerts A Sá | 7 | 3 | 7 | ||||||||||||||||||||
| 3 | D Macpherson R Reneberg | 6 | 6 | 3 | D Macpherson R Reneberg | 6 | 6 | 6 | |||||||||||||||||||
 J Burillo A Martín | 1 | 3 | N Aerts A Sá | 6 | 7 | ||||||||||||||||||||||
| S Davis A O'Brien | 6 | 6 | D DiLucia M Sell | 2 | 6 | ||||||||||||||||||||||
D Bowen  Ó Ortiz | 3 | 4 | S Davis A O'Brien | 5 | 4 | ||||||||||||||||||||||
| D DiLucia M Sell | 4 | 6 | 7 | D DiLucia M Sell | 7 | 6 | |||||||||||||||||||||
| 2 | G Kuerten F Meligeni | 6 | 1 | 5 | |||||||||||||||||||||||
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