A switchable diffuser is provided and includes: a first substrate; a second substrate; a first driving electrode on the first substrate; a second driving electrode on the second substrate; a polymer dispersed liquid crystal film between the first and second driving electrodes. The polymer dispersed liquid crystal film is made of a polymer dispersed liquid crystal composition via polymerizing and curing; the polymer dispersed liquid crystal composition includes: polymerized monomer, photoinitiator, spacer particles, nano scattering particles and liquid crystal. In the polymer dispersed liquid crystal composition, a percentage of the polymerized monomer is 5 wt %˜30 wt %, a percentage of the photoinitiator is 0.05 wt % to 3 wt %, a percentage of the spacer particles is 0.8 wt % to 2 wt %, a diameter of the spacer particles is in a range of 10 micrometers to 50 micrometers, a percentage of the nano scattering particles is 0.1 wt % to 2 wt %, a percentage of the liquid crystal is 69 wt % to 90 wt %.