The 1998 Campionati Internazionali di San Marino was a men's tennis tournament played on outdoor clay courts in City of San Marino, San Marino that was part of the World Series of the 1998 ATP Tour. It was the tenth edition of the tournament and was held from 10 August until 16 August 1998. Third-seeded Dominik Hrbatý won the singles titles.
See main article: 1998 Campionati Internazionali di San Marino – Singles. 
Dominik Hrbatý defeated 
Mariano Puerta, 6–2, 7–5
See main article: 1998 Campionati Internazionali di San Marino – Doubles. 
Jiří Novák / David Rikl defeated Mariano Hood / Sebastián Prieto, 6–4, 7–6