Abstract: In this paper the extraction mechanism of uranium from carbonate solutions containing hydrogen peroxide, oxalate, fluoride, nitrate, chloride and sulfate by trialkyl-methyl ammonium chloride (alkyl radicals C9 to C11)in kerosene is studied. When C2O2--4, F,- NO3-, Cl- and SO24-are added to the uranyl carbonate solution, the uranyl ion exists only in the form of UO 2 (CO3)34,as shown by the absorption spectrum of the solution, The ex-tractable complex (R.4N)4 UO2 (CO3)3 is formed during extraction. When hydrogen peroxide is added to the solution mentioned above, the absorption spectrum undergoes great change. The color of the solution varies from yellow ot rose-red. This fact indicates that the complex ion UO2 (CO3)34- forms a new complex with hydrogen peroxide. Based on the experimental results, we assume that UO 2 (O2) (CO 3)24- ion is formed and uranium is extracted in the form of (R4N)4 UO2 (O2) (CO3)2. The mole ratio of R4N+: UO22+ is equal to 4:1. This conclusion is confirmed by the method of isomolar series, the saturated extraction method and the usual slope method.The effect of various factors on the extraction percentage has been determined, namely the concentration of alkyl ammonium salt in/kerosene, uranium saturated concentration, variation in the composition of the diluent and the content of various anions.The experimental results are as follows: the extraction percentage of uranium is greater than 95% at a concentration of sodium carbonate less than 20 g/1 and the concentration of the alkylammonium salt greater than 5%. It decreases sharply with an increase in the concentration of carbonate and decreases slowly with an increase in the uranium concentration in the aqueous phase. Other anions such as F-, Cl-, C2O42- SO42- and NO3-have only slight effect.The addition of 15% long chain secondary alcohol (C12-C16) to the organic phase is necessary for increasing the solubility of alkylammonium salt and its extractable species in kerosene as well as for avoiding emulsion and third phase formation.This work may be useful for the recovery of uranium from waste water and the leaching solution of uranium ores. ,