A facile method to prepare monodisperse speckled colloids has been developed via one-step seeded polymerization from noncross-linked latex particles. It was found that both cross-linking agents in the added monomer mixture and charged initiation species are essential for the formation of speckles on composite latex particle surface in seeded polymerization. The size and number density of speckles on the surface are tunable by adjusting the concentration of surfactant. A possible mechanism for the formation of such speckled colloids has been proposed based on a series of control experiments. Speckled colloidal particles were used as substrates for the adsorption of tobacco mosaic virus, and a much stronger adsorption was observed compared to smooth particles, implying a potential application of these speckled particles in virus collection and more.