Disclosed herein are a quantum dot unit having an improved structure for improving color reproducibility, a quantum dot sheet having the same, and a display device having the quantum dot unit or the quantum dot sheet. The display device includes a display panel configured to display an image, a light source provided to emit light to the display panel, a light guide plate provided to guide the light emitted from the light source to the display panel, and a quantum dot unit disposed between the light source and the light guide plate to change a wavelength of the light emitted from the light source and having ductility, wherein the quantum dot unit includes a glass fiber having a hollow portion and a quantum dot accommodated in the hollow portion.