The 1984 NCAA Division I baseball tournament was played at the end of the 1984 NCAA Division I baseball season to determine the national champion of college baseball. The tournament concluded with eight teams competing in the College World Series, a double-elimination tournament in its thirty eighth year. Eight regional competitions were held to determine the participants in the final event. Six regions held a four team, double-elimination tournament while two regions included six teams, resulting in 36 teams participating in the tournament at the conclusion of their regular season, and in some cases, after a conference tournament. The thirty-eighth tournament's champion was Cal State Fullerton, coached by Augie Garrido. The Most Outstanding Player was John Fishel of Cal State Fullerton.
Bold indicates CWS participant.
The opening rounds of the tournament were played across eight regional sites across the country, six consisting of four teams and two of six teams. The winners of each Regional advanced to the College World Series.
Bold indicates winner.
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The following players were members of the All-Tournament Team.
Gary Green and Bill Swift appear in their fourth College World Series. Michigan's appearance was the last for the Big Ten until 2013 when Indiana made the College World Series.