The preparation of ultra.fine particles of salbutamol sulphate(SS)was accomplished with a reactive precipitation pathway,in Which salbutamo]and sulphuric acid were used as reactants wlth the solvents of ethanol.The effects of sulphuric acid concentration.reaction temperature,stirring rate,and reaction time on the Size of the particle were investigated.A binary mixture composed of lactose and SS was prepared to evaluate SS.The results showed that ultra-fine SS particles with controlled diameters ranging between 3 grn and 0.8 μm and with a narrow distribution could be achieyed.The morphology consisting of clubbed particles was successfully obtained.The pu-fity of the particles reached above 98%with UV detection.The dose of dry powder inhalation was obtained by blending the particles with recrystallized lactose.which acted as a carrier.The deposition quantity of the drug in breathing tract was estimated using a twin impinger apparatus.Compared wlth the Shapuer powder(purchased in the market),the results showed that SS particles had more quantines subsided in simulative lung.