The 1978 Italian Open was a combined men's and women's tennis tournament that was played by men on outdoor clay courts at the Foro Italico in Rome, Italy. The men's tournament was part of the 1978 Colgate-Palmolive Grand Prix while the women's tournament was part of the Colgate International Series (Category A). It was the 35th edition of the tournament and was held from 22 May through 28 May 1978. The singles titles were won by first-seeded Björn Borg, who won his second Italian Open title after 1974, and third-seeded Regina Maršíková.[3][4]