The invention provides Iboga alkaloid or pharmaceutically acceptable salt thereof, a preparation method and application thereof, an iboga alkaloid pharmaceutical composition and application thereof, and belongs to the technical field of medicines. The iboga alkaloid provided by the invention has no obvious inhibitory activity on a candida albicans fluconazole drug-resistant strain; however, when fluconazole and iboga alkaloid jointly act on the candida albicans fluconazole drug-resistant strain, the drug resistance of the candida albicans fluconazole drug-resistant strain is improved; the inhibition rate of the iboga alkaloid on the candida albicans fluconazole drug-resistant strain is as high as 99.7%, so that the iboga alkaloid provided by the invention has very strong drug-resistant reversal activity on the candida albicans fluconazole drug-resistant strain, and is a candidate drug which has development potential and can reverse the drug resistance of the candida albicans fluconazole drug-resistant strain.