The development of antimicrobial coatings in various sectors is escalating nowadays. However, design, synthesis, and fabrication of simple antimicrobial polymer coatings with potent biocidal action against pathogenic microbes are necessary to emerge. The current article deals with fabrication of high efficient ultrathin coatings of synthesized polymer for controlling pathogenic bacteria and fungi. The article is intensified with simple synthesis, characterization, fabrication of ultrathin coatings and their antimicrobial studies. The polymer structure is elucidated by FTIR, 1 HNMR, and 13 CNMR, and the thermal properties are explained by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The antimicrobial activity of a polymer and their ultrathin coatings against Escherichia coli, Staphylococcus aureus, tubercular-variant Mycobacterium smegmatis, and Candida albicans are reported elaborately. The morphology of ultrathin coating and their interaction with microorganisms are studied using a scanning electron microscope and an atomic force microscope.