The 1999 Croatian Bol Ladies Open singles was the singles event of the sixth edition of the Croatian Bol Ladies Open, a WTA Tier IV tournament and the most prestigious women's tennis tournament held in Croatia. Mirjana Lučić was the two-time defending champion, but she did not compete this year.
Corina Morariu won the title after losing in the final the previous two years, defeating first seed Julie Halard-Decugis.
