New layered perovskite compounds, Ag x Na 2-x La 2 Ti 3 O 10 (x=0.2,0.3 and 0.5) were synthesized by an ion-exchange reaction of Na 2 La 2 Ti 3 O 10 with AgNO 3 solution and characterized by energy dispersive X-ray analysis(EDX), X-ray diffractometry(XRD), scanning electron microscopy(SEM) and X-ray photoelectron spectroscopy(XPS). The ion-exchange processes were optimized, and the antibacterial activity, light permanency and water-resistance were evaluated. Surprisedly, no significant changes in crystal structure of Na 2 La 2 Ti 3 O 10 are found by the exchange of silver ions. The Ag 0.3 Na 1.7 La 2 Ti 3 O 10 particles conglomerate obviously with irregular shape and size. Ag 0.3 Na 1.7 La 2 Ti 3 O 10 , possessing the minimum inhibitory concentrations(MICs) against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) of 180 mg/L and 240 mg/L, has high antibacterial activity, good light permanency and water-resistance. The ionic state silver in Ag x Na 2-x La 2 Ti 3 O 10 is the antibacterial active component.