Monoatomic amorphous metals (MAM) are highly desirable for gaining fundamental understandings of amorphous metals. To date, only a handful of metals have been successfully made into MAMs, which, however, are either limited to very small yields/sample sizes (e.g., 10 nm) or highly unstable at ambient conditions. Here we report a simple and effective solution-based anodization method for synthesizing MAMs by rapidly reducing the corresponding metal ions during the discharge approach. MAMs are conveniently produced at a large quantity with a diameter up to the sub-micron scale, representing a drastically enhanced sample volume, opening new possibilities for the research of amorphous metals.