1998 (MCMXCVIII) was a common year starting on Thursday of the Gregorian calendar, the 1998th year of the Common Era (CE) and Anno Domini (AD) designations, the 998th year of the 2nd millennium, the 98th year of the 20th century, and the 9th year of the 1990s decade.

1998 was designated as the International Year of the Ocean.