It is intended to provide thermotolerant and antimicrobial proteins having a broad antibacterial spectrum and being useful in the agricultural, medical and industrial field; and plants resistant to pathogenic microorganisms. Namely, DNAs comprising the base sequences represented by SEQ ID NOS: 1 to 5 respectively; antimicrobial proteins encoded by these DNAs; and fungicides, antibacterial agents and antibacterial/antifungal agents for industrial use comprising the antimicrobial proteins as the active ingredient.