A detachable loudspeaker and metal detector includes a loudspeaker assembly detachably installed outside a control box. The loudspeaker assembly includes an outer protective shell, an inner protective shell, and a dynamic loudspeaker. The outer and inner protective shells form an accommodating cavity in which the dynamic loudspeaker is installed. The inner protective shell is facing the control box, which is equipped with a PCB board. The dynamic loudspeaker is electrically connected to the PCB board through terminal wires. A detachable component is arranged on the outer protective shell to detachably fix the outer protective shell to the control box. When the loudspeaker assembly is damaged and needs to be replaced, it can be detached from the control box without opening the control box, which greatly improves the inconvenience of replacing the loudspeaker assembly.