This list of 1998 motorsport champions is a list of national or international auto racing series with a Championship decided by the points or positions earned by a driver from multiple races.
| Series | Driver | Season article |
|---|---|---|
| Professional SportsCar Racing Championship | WSC:  Butch Leitzinger | 1998 IMSA GT Championship season |
GT1:  Andy Wallace | ||
| GT2: Larry Schumacher | ||
| GT3: Mark Simo | ||
| United States Road Racing Championship | Can-Am: James Weaver | 1998 United States Road Racing Championship season |
GT1:  Thierry Boutsen | ||
| GT2: Scott Sansone GT2: Cameron Worth | ||
GT3:  Ross Bentley | ||
| International Sports Racing Series | SR1:  Emmanuel CollardSR1:  Vincenzo Sospiri | 1998 International Sports Racing Series season |
| SR1 Teams: JB Giesse Team Ferrari | ||
| SR2: Jean-Claude de Castelli | ||
| SR2 Teams: Waterair Sport | ||
| FIA GT Championship | GT1:  Klaus LudwigGT1:  Ricardo Zonta | 1998 FIA GT Championship season |
GT2:  Olivier BerettaGT2:  Pedro Lamy | ||
| GTR Euroseries | Thomas Bscher | |
| All Japan GT Championship | Érik Comas Masami Kageyama | |
| British GT Championship | GT1: Steve O'Rourke GT1: Tim Sugden | |
| GT2: Richard Dean GT2: Kurt Luby | ||
| Trans-Am | Paul Gentilozzi | |
| Porsche Supercup, Porsche Carrera Cup, GT3 Cup Challenge and Porsche Sprint Challenge | ||
| Porsche Supercup | Patrick Huisman | 1998 Porsche Supercup |
| Teams: Olaf Manthey Racing | ||
| Porsche Carrera Cup France | Dominique Dupuy | 1998 Porsche Carrera Cup France |
| Porsche Carrera Cup Germany | Dirk Müller | 1998 Porsche Carrera Cup Germany |
| Teams: UPS Porsche Junior Team | ||
| Series | Driver | Season article |
|---|---|---|
| European Truck Racing Championship | Super-Race-Trucks: Ludovic Faure | 1998 European Truck Racing Championship |
| Race-Trucks: Heinz-Werner Lenz | ||
| Fórmula Truck | Oswaldo Drugovich Jr. | 1998 Fórmula Truck |
| Teams: Drugovich Auto Peças | ||
| Series | Driver | Season article |
|---|---|---|
| NASCAR Winston Cup Series | Jeff Gordon | 1998 NASCAR Winston Cup Series |
| Manufacturers: Chevrolet | ||
| NASCAR Busch Grand National Series | Dale Earnhardt Jr. | 1998 NASCAR Busch Series |
| Manufacturers: Chevrolet | ||
| NASCAR Craftsman Truck Series | Ron Hornaday Jr. | 1998 NASCAR Craftsman Truck Series |
| Manufacturers: Chevrolet | ||
| NASCAR Busch North Series | Mike Stefanik | 1998 NASCAR Busch North Series |
| NASCAR Winston West Series | Kevin Harvick | 1998 NASCAR Winston West Series |
| ARCA Bondo/Mar-Hyde Series | Frank Kimmel | 1998 ARCA Bondo/Mar-Hyde Series |
| AUSCAR |  Darren McDonald | 1997–98 AUSCAR season |
| Australian Super Speedway Championship | Kim Jane | 1997–98 Australian Super Speedway Championship |
| Turismo Carretera |  Guillermo Ortelli | 1998 Turismo Carretera |
| Series | Driver/Co-Driver | Season article |
|---|---|---|
| World Rally Championship |  Tommi Mäkinen | 1998 World Rally Championship |
| Manufacturer: Mitsubishi | ||
| FIA Cup for Production Cars |  Gustavo Trelles | |
| New Zealand Rally Championship |  Geoff Argyle | 1998 New Zealand Rally Championship |
| Co-Drivers: Alan Glen | ||
| Series | Rider | Season article | |
|---|---|---|---|
| 500cc World Championship | Michael Doohan | 1998 Grand Prix motorcycle racing season | |
| 250cc World Championship | Loris Capirossi | ||
| 125cc World Championship | Kazuto Sakata | ||
| Superbike World Championship | Carl Fogarty | 1998 Superbike World Championship season | |
| Supersport World Series | Fabrizio Pirovano | ||
| Speedway World Championship |  Tony Rickardsson | 1998 Speedway Grand Prix | |
| AMA Superbike Championship | Ben Bostrom |
| Series | Champion | Refer |
|---|---|---|
| NHRA Winston Drag Racing Series | Top Fuel: Gary Scelzi | 1998 NHRA Winston Drag Racing Series |
| Funny Car: John Force | ||
| Pro Stock: Warren Johnson | ||
| Pro Stock Motorcycle: Matt Hines | ||
| Series | Driver | Season article |
|---|---|---|
| CIK-FIA Karting World Championship | FSA: Davide Forè | |
| FC: Gianluca Beggio | ||
| Formula A: Ruben Carrapatoso | ||
| CIK-FIA Karting European Championship | FSA: Davide Forè | |
| FC: Gianluca Beggio | ||
| FA: César Campaniço | ||
| ICA: Julien Poncelet | ||
| ICA-J: Frank Pereira | ||
| Cadet: Álvaro Parente | ||
Alexander Nesterov
Robert Lechner
Ramón Ibarra
Carlos Perea
Michael Pedersen
