Abstract: The present invention provides a process for removing an oxygen-containing component in a crude organometallic compound consisting essentially of an organometallic compound of the general formula (1):R.sub.1 R.sub.2 MX (1)wherein R.sub.1 and R.sub.2 independently represent an alkyl group or a cycloalkadienyl group, M represents a Ga atom or an In atom and X represents an alkyl group, a halogen atom or a hydrogen atom, and the oxygen-containing component as an impurity, which comprises the steps of mixing the crude organometallic compound and an alkali halide in an amount of 0.1 to 10% by weight of the crude organometallic compound, heat-treating the mixture, and vaporizing the organometallic compound for separation, the steps being carried out in a substantially oxygen-free atmosphere.