p-Aminophenyl thiocyanate and 2-chloro-4-aminophenyl thiocyanate were diazotized and reacted with 2, 5-dichlorophenol or with ο-or m-bromophenol in neutral or weak alkalinity to obtain azophenol derivatives (IV to VIII). 4-Amino-2, 6-dichlorophenyl thiocyanate was diazotized and similarly reacted with 2-chlorophenol to obtain IX. Antibacterial activity of these compounds and other compounds synthesized to date (I to XXXVI) was tested on Staphylococcus aureus and Bacillus subtilis. The minimum concentration inhibiting the growth of these bacteria was 6.25μg./ml, in p-(2-chloro-4-hydroxyphenylazo) phenyl thiocyanate, and 6.25 μg./ml. against Staph. aureus in 2-bromo-4-amino-5-(p-chlorophenoxy)-phenyl thiocyanate.