In order to produce molten metal from all types of metal carriers used in metallurgy, and in particular from a wide range of quantitative combinations, an installation for producing molten metal comprises the following components: an electric arc furnace (1) having a charge opening (11, 21) for molten metal and/or scrap and/or directly-reduced metal, especially directly-reduced iron and/or ore, and at least one electrode (16) and a slag tapping unit (22); and an oxygen lancing converter vessel (3) fitted with a slag tapping unit (41). Said oxygen lancing converter vessel (3) forms a single unit with the electric arc furnace (1) which unit is connected by means of an overflow weir (34) and rigidly mounted on the base. The bath surface specifically related to bath volume is smaller in the oxygen lancing converter vessel (3) than in the electric arc furnace (1). Lastly, the oxygen lancing converter vessel (3) shares a common reaction chamber with the electric arc furnace (1), which chamber is situated above the bath level of the two vessels.