Particle Counting and Laser Diffractometry were employed to derive the fractal dimension of agglomerated particles. Particle counting and laser diffractometry provide straightforward information relative to the volume of the solid matter, which is dispersed in the total volume of the agglomerate including solid matter and inner voids, respectively. Experimental results concern aggregates of polystyrene latex particles initially dispersed in electrolyte or polyelectrolyte solutions. The fractal dimension of aggregates obtained under perikinetic conditions was determined to be 2.12 while that of aggregates obtained under othokinetic conditions was determined to be a function of the electrolyte concentration of the latex suspension. The values of 1.4 and 1.8 were derived for non restructuring and reconforming systems, respectively. The experimental values of the fractal dimension were found to agree with those derived for clusters generated by numerical simulations.