Morphology of the conducting polymer PEDOT:TOS (poly(3,4-ethylenedioxythiopherre) doped with molecular, tosylate) and its crystallization in aqueous solution, were Studied using atomistic molecular dynamics simulations. It was foirnd that (a) PEDOT comprises crystallite aggregates consisting of 3-6 pi-pi stacked chains. The crystallites are linked by interpenetrating pi-pi stacked chains such that percolative paths in the structure are formed. (b) The size of the crystallites.deperids on the water content, but the pi-pi stacking distance is practically independent of the chain length, charge,Concentration and water content. (c) TOS counterions are located either on the top of the,chains or on the side of the crystalliteS and their distribution depends on the charge concentration but is practically independent of the water content; (d) PEDOT depends On their length and water,content. 2 chains and crystallites exhibit bending that depends On their length and water content.