We studied the aggregation behavior of hexadecane droplets after adding phosphatidylcholine (PC) vesicles to the suspension medium by dynamic light scattering electrophoresis, leakage test of fluorescence, and surface tension measurements. The variable factors in these experiments were (i) the concentration of LaCl3 into the bulk, (ii) the concentrations of the PC vesicles, and (iii) the size of the PC vesicles. The experimental results indicated that during the initial stage of adsorption, PC vesicles hold well-integrated into the aggregates and then they disintegrate gradually into a monolayerlike structure, although the latter process is a relatively slow one. It is concluded that the initial aggregation of emulsion droplets after adding PC vesicles is due to the interparticle bridging induced by the adsorbed PC vesicles.