<p>The effect of antibacterial adhesive on the biological corrosion resistance of mortar in seawater environment was studied by means of scanning electron microscope, thermogravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy, and ultra-depth microscope. The results show that the antibacterial adhesive can effectively inhibit the growth of sulfur-oxidizing bacteria in seawater, hinder their metabolism to produce biological sulfate, and reduce the formation of destructive product gypsum. The mineral composition and thermal analysis showed that the peak value of plaster diffraction peak and the mass loss of plaster dehydration in antibacterial adhesive group were significantly lower than those in blank group (without protective coating group). In addition, the electric flux of chloride ions (&gt; 400 C) in the blank group of mortar samples was higher than that in the antibacterial adhesive group (&lt; 200 C), indicating that the antibacterial adhesive can effectively reduce the permeability of chloride ions in mortar, and thus hinder the Cl⁻ erosion in seawater.</p>