We synthesized polycyclosiloxanes with varying catechol substitution ratios (CFPSs) and investigated silver nanoparticles (AgNPs) adsorption ability on their self-assembled nanofilm. The nanoparticle adsorption ability as a function of the catechol substitution ratio was examined using SEM and a tape peeling test. It was evidenced that the substitution ratio of the catechol units was directly proportional to the surface density of AgNPs adsorbed on CFPS nanofilms.