The adsorption of a nonplanar biocolloid on a rigid collector surface is evaluated theoretically. Here, a biocolloid consists of a rigid core and an ion-penetrable membrane carrying nonuniformly distributed fixed charges. Both a biocolloid and a collector are immersed in an electrolyte solution. The simulated results demonstrate that based on constant total amount of fixed charges in the membrane phase, the classical point-charge model overestimates the rate of adsorption. The larger the curvature of a biocolloid, the faster the rate of adsorption, and the adsorption rate calculated for a cylindrical surface is faster than that for a corresponding spherical one. The greater the nonuniformity of the distribution of fixed charges, the longer the time required for biocolloidal adsorption, and the adsorption time evaluated for a nonlinear distribution of fixed charges is longer than that for a corresponding linear one. Thin membrane, high average concentration of fixed charges, low permittivity of dielectric medium and large sizes of cations, anions and fixed charges lead to slow rates of adsorption. (C) 2003 American Institute of Physics.