In this work, activated carbons (ACs) containing silver were prepared by anodic oxidation and immersion processes in AgNO$_3$ solution, in order to improve the ammonia removal efficiency and increase their antibacterial activities. The pore and surface properties of ACs were studied in terms of N2/77k nitrogen adsorption measurement, X-ray photoelectron spectrometer (XPS), and scanning electron microscope (SEM). The ammonia removal efficiency was confirmed by gas-detecting tube technique and the antibacterial activities were investigated by dilution test against Staphylococcus aureus (S. aureus; gram positive and virulence) and Klebsiella pneumoniae (K. pnumoniae; gram negative and avirulence). As a result, the specific surface area and micropore volume of ACs decreased slightly with the AgNO$_3$ treatment. However, the AgNO$_3$ treated ACs led to an increase in ammonia removal efficiency, mainly due to an increase in oxygen containing functional groups on ACs surfaces. Also, the antibacterial activities of the AgNO$_3$ treated ACs agianst S. aureus as well as K. pnumoniae predominantly increased, which could be attributed to the presence of silver in Ag/ACs systems.