Poly urea-formaldehyde was synthesized simply and rapidly from urea and formaldehyde by condensation polymerization and studied for the sorption of trace acid blue from aqueous solution. The optimum pH value for sorption of the acid blue was 4. Experimental results showed that the sorption capacity of poly urea-formaldehyde for acid blue was determined. The synthetic polymer can be reused for 5 cycles of sorption-desorption without any significant change in sorption capacity. The equilibrium adsorption data of acid blue on poly urea-formaldehyde were analyzed by Langmuir models. Based on equilibrium adsorption data the Langmuir constants were determined about 19 L.mg-1 at pH 4 and 20°C.