Objective To design and synthesize novel Hsp90 inhibitors with dual functions of synergistically enhancing the antifungal activity of fluconazole （FLC） against drug-resistant fungi and anti-tumor activity based on the Hsp90 inhibitor Ganetespib. Methods The previous research found that Ganetespib had a good synergistic anti-resistant fungal activity with FLC, with a fractional inhibitory concentration index （FICI） of 0.023 to 0.039. In this study, structural modifications were made to Ganetespib by replacing its indole ring with a phenyl ring containing different substituents to design and synthesize a series of new compounds. The in vitro synergistic anti-resistant fungal activity against C. albicans 0304103 in combination with FLC, anti-tumor activity （against HEL, HL60 and A549 cells）, and Hsp90α inhibition activity were determined to explore their structure-activity relationship and mechanism of action. Results The chemical structures of 19 new compounds were confirmed by ¹H NMR, ¹³C NMR and HRMS. Most of the compounds exhibited strong Hsp90α inhibitory activity, good synergistic activity against drug-resistant fungi in combination with FLC and anti-tumor activity. The substitution of electron-donating groups on the benzene ring was beneficial to enhancing the synergistic activity against drug-resistant fungi in combination with FLC. Among them, compounds F3 and F5 showed excellent synergistic activity against drug-resistant fungi in combination with FLC （FICI were both 0.047） and anti-tumor activity （IC₅₀ were 0.025 to 0.15 μmol/L and 0.021 to 0.23 μmol/L respectively）, and could down-regulate the expression levels of drug resistance genes and efflux pump genes in fungi, inhibit the formation of fungal biofilms, and arrest the cell cycle of HEL cells at G0/G1 phase. Conclusion The novel Hsp90 inhibitors such as F3 and F5 could both effectively exert the dual activities of synergizing with FLC to combat drug-resistant fungi and fight against tumors, which provided a new idea for the development of new drugs with dual functions of synergizing with FLC to combat drug-resistant fungi and fight against tumors.