Main purpose of this research is to investigate dyeing properties, colour fastness values (light, water, perspiration, chlorinated water, rubbing, washing) and antibacterial activity of cotton fiber fabric dyed with water-soluble zinc phthalocyanine containing azo groups (Azo-ZnPc). It is expected that zinc metal ion and azo groups present simultaneously in one phthalocyanine (Pc) structure can ensure antibacterial effect on cotton fabric. Literature survey shows that this Azo-ZnPc structure was not used before as a dyestuff in textile colouration. Therefore, synthesis and investigation some properties of this dye could be worthwhile. In this study firstly, the Azo-ZnPc was synthesized and the structure was verified with FT-IR, UV/vis, mass spectra and H-1-NMR, C-13-NMR studies. Afterwards, the cotton fabric modified with a cationic auxiliary was dyed with the Azo-ZnPc in the presence of sodium carbonate via exhaustion process. Finally, the colour fastness values were determined according to ISO standards and color strength (K/S values), L, a*, b*, C*, h* values measurements were performed. Antibacterial properties of the uniformly green coloured fabric were examined according to AATCC 100 standard. Significant reduction of Staphylococcus aureus (S. aureus) and Klebsiella pneumoniae (K. pneumoniae) bacteria, rated as 99.99 %, 99.74 %, respectively, were observed on cotton fiber fabric.