Display module and display device are provided. The display module includes a display panel, first dimming areas and a second dimming areas. The display panel includes a display array including a plurality of sub-pixels with pixel gaps between adjacent sub-pixels. Both a first dimming area and a second dimming area include at least one of the plurality of sub-pixels. The first dimming area includes a first dimming layer with a refractive index of n1, a second dimming layer with a refractive index of n2. A contact interface between the first dimming layer and the second dimming layer includes a first dimming structure. The second dimming area includes a third dimming layer with a refractive index of n3, and a fourth dimming layer with a refractive index of n4. A contact interface between the third dimming layer and the fourth dimming layer includes a second dimming structure.