The invention provides a detection device for mobile phone shells, including a bottom plate, a first installation component which is arranged above and connected with the bottom plate and is providedwith a first installation slot, a positioning component which is arranged in the first installation slot to support a mobile phone shell, a second installation component which is arranged to the sideof the first installation component and connected with the bottom plate and is provided with at least one second installation slot, and instruments which are arranged in the second installation slotsto detect the size parameters of the mobile phone shell, wherein the second installation component and the bottom plate are of an integrated structure. According to the technical scheme provided by the invention, the mobile phone shell is positioned by the positioning component; the measuring ends of the instruments are in contact with the mobile phone shell so that the mobile phone shell can be conveniently measured; the deviation of the inner length and width and the outer profile relative to the reference center line can be quickly and effectively detected; and the production efficiency canbe greatly improved.