Cycloadducts of 3-Hydroxy-1-phenacyl pyridinium bromide (1) and 3-Hydroxy-1-(4-nitrobenzyl) pyridinium chloride (2) with vinyl trimethylsilane, methyl sulfonyl chloride and vinyl triphenylphosphonium bromide were prepared. Six novel polyaniline/ cycloadduct (PANI/CY) composites were prepared by the polymerization of aniline in the presence of different weight percentages of cycloadduct were characterized using Fourier transform infrared (FTIR) spectroscopy, Mass spectrum (MS) and Nuclear magnetic resonance (NMR),Transmission electron microscopy (TEM). Their potential as antibiofouling agents was evaluated. Antimicrobial /macrobial fouling activity were conventional using inhibition zone, serial tube dilution methods and mortality tests respectively.