| Competition: | Serie A |
| Season: | 1998–99 |
| Winners: | Milan 16th title |
| Dates: | 12 September 1998 – 23 May 1999 |
| Relegated: | Salernitana Sampdoria Vicenza Empoli |
| Continentalcup1: | Champions League |
| Continentalcup1 Qualifiers: | Milan Lazio Fiorentina Parma |
| Continentalcup2: | UEFA Cup |
| Continentalcup2 Qualifiers: | Roma Udinese Bologna |
| Continentalcup3: | Intertoto Cup |
| Continentalcup3 Qualifiers: | Juventus Perugia |
| League Topscorer: | Márcio Amoroso (22 goals) |
| Matches: | 306 |
| Total Goals: | 845 |
| Prevseason: | 1997–98 |
| Nextseason: | 1999–2000 |
The 1998–99 Serie A saw Milan win their 16th Scudetto, led by coach Alberto Zaccheroni. Lazio finished second, losing the title on the last day. Internazionale, with an often injured or rested Ronaldo, had a disastrous season, finishing in 8th position, whereas Juventus' impressive start was cut short by a bad injury to Alessandro Del Piero, and they wound up having an unimpressive season.
Salernitana, Venezia, Cagliari and Perugia had been promoted from Serie B.
| Team | Head Coach | Kit manufacturer | Shirt sponsor | |
|---|---|---|---|---|
| Bari |  Eugenio Fascetti | Lotto | TELE+ | |
| Bologna | Carlo Mazzone | Diadora | Granarolo | |
| Cagliari | Biemme | Pecorino Sardo | ||
| Empoli | Errea | Sammontana | ||
| Fiorentina | Fila | Nintendo | ||
| Inter | Roy Hodgson | Nike | Pirelli | |
| Juventus | Carlo Ancelotti | Kappa | D+ | |
| Lazio |  Sven-Göran Eriksson | Puma | Cirio | |
| Milan | Alberto Zaccheroni | Adidas | Opel | |
| Parma | Alberto Malesani | Lotto | Parmalat | |
| Perugia | Vujadin Boškov | Galex | None | |
| Piacenza | Giuseppe Materazzi | Lotto | Copra (Home)/Gruppo DAC (Away) | |
| Roma |  Zdenek Zeman | Diadora | INA Assitalia | |
| Salernitana | Francesco Oddo | Asics | Exigo Jeans & Casual | |
| Sampdoria | Asics | Daewoo Matiz | ||
| Udinese | Francesco Guidolin | Diadora | Telital | |
| Venezia | Walter Novellino | Kronos | Emmezeta | |
| Vicenza | Edoardo Reja | Biemme | Belfe |
6th and 7th of Serie A:----
Coppa Italia Third place:----
Udinese and Bologna qualified to 1999–2000 UEFA Cup, while Juventus qualified for the 1999 UEFA Intertoto Cup.
