Background: The aim of this study was to investigate the effect of extracts from the biotechnologically obtained Arthrospira platensis (spirulina) biomass with metals, on some strains of filamentous fungi causing invasive mycoses. Material and methods: The extracts from spirulina biomass were used as material. The agar diffusion method was used to identify antifungal activity of extracts. Five strains of filamentous fungi were used as test objects. The level of toxicity was evaluated based on the quantitative determination of the activity of extracellular lactate dehydrogenase (LDH). Results: The ethanol extracts from biomass of spirulina containing chromium, copper, cadmium, cobalt, zinc and iron, have antifungal activity against Aspergillus fumigatus CNM-FA-02, Mucor vulgaris CNMN-FD-07, Penicillium expansum CNMN-FD-05, Fusarium solani and Fusarium oxysporum. At the same time, the extracts from standard biomass are inactive (exception: the ethanol extract slightly suppresses the growth of Aspergillus fumigatus CNM-FA-02). Naftifine hydrochloride was used as a control. We found four variants with higher antifungal activity than naftifine hydrochloride. In the case of biomass extracts containing copper, cobalt, chromium and cadmium the inhibition of fungal growth was associated with increased activity of extracellular LDH. Conclusions: Extracts from biomass containing metals are characterized by various antifungal activities, inhibiting the fungal growth and increasing the release of lactate dehydrogenase into the extracellular medium.