There is disclosed a process for producing silanes by reducing polyhalosilane with a mixture of alkyl aluminum hydride and trialkyl aluminum, in which a treatment for reducing the content of trialkyl aluminum in the mixture is lowered to 10 mol. % or less of alkyl aluminum hydride prior to the reduction reaction.As to methods for reducing the content of trialkyl aluminum in the mixture, there are provided, for example, distillation, recrystallization, separation by complex formation, pyrolysis of trialkyl aluminum and decomposition by hydrogenation of trialkyl aluminum.