Abstract: To investigate the antibacterial properties of propagule extracts of Eurotium cristatum, we determined the antibacterial activity of extracts from different Eurotium cristatum propagules (e.g., ascocarps, ascospores, and conidia) against Staphylococcus aureus, Escherichia coli, Candida albicans, Streptomyces albus, Micrococcus luteus, and Bacillus subtilis using the disk diffusion test. Additionally, we explored the stability of their active antibacterial ingredients under different temperatures, duration of exposure to ultraviolet light, and pH. Eurotium cristatum propagules were disrupted using a glass bead-beating method to prepare the water extracts of ascocarps, ascospores, and conidia. The results suggested that the extracts of ascocarps and ascospores exerted significant antibacterial effects, primarily against M. luteus, S. aureus, and E. coli. Moreover, these extracts could maintain stable antibacterial activity at 25-80 ℃ and pH 2-6. However, the extract of conidia lacked any antibacterial effect. In conclusion, the sexual propagules (ascocarps and ascospores) of Eurotium cristatum contain active antibacterial ingredients that exhibit promising stability under certain pH and temperature ranges.