An adjustment structure for depth of field, a display device, and a control method thereof. The adjustment structure for depth of field includes: a first substrate, a second substrate and a lens layer located between the first substrate and the second substrate. The lens layer includes a plurality of lens units; each of the plurality of lens units includes two electrodes and a lens located between the two electrodes with an adjustable focal length; the lens includes charged particles and a first transparent insulating liquid encapsulated by a transparent flexible film; the charged particles include positively charged particles and negatively charged particles.