2 H -[1,2,3]Triazolo[4,5- g ]isoquinoline-4,9-diones and 2 H -[1,2,3]triazolo[4,5- g ]quinoline-4,9-diones were synthesized and tested for in vitro antifungal activity against pathogenic fungi. Many of those synthesized showed potent antifungal activity. Compounds 3a , 3b , 3g , and 3h completely inhibited the growth of all fungal species tested at the MIC level of 0.8–12.5 µg/mL. The results suggest that 2 H -[1,2,3]triazolo[4,5- g ]isoquinoline-4,9-diones could be antifungal agents.