The invention discloses a converting process and device for copper matte bottom blowing. The converting process for copper matte bottom blowing comprises the following steps: adding liquid copper matte to a copper matte bottom blowing device of a copper matte bottom blowing converting furnace by using copper matte ladle; adding a flux into the copper matte bottom blowing device of the copper matte bottom blowing converting furnace; continuously blowing oxygen-containing gas into the melt in the copper matte bottom blowing device of the copper matte bottom blowing converting furnace from the bottom of the copper matte bottom blowing device of the copper matte bottom blowing converting furnace by using a bottom blowing spray gun; and respectively discharging crude copper and converting slag from the copper matte bottom blowing device of the copper matte bottom blowing converting furnace. The converting process and device for copper matte bottom blowing provided by the invention can realize continuous converting of copper matte, and have the advantages of small amount of generated flue gas, stable SO2 concentration, environment-friendliness, high efficiency, and low production cost of crude copper and sulfuric acid.