The present disclosure provides a light collimation device, a backlight module, and a display device, and relates to the field of display technology. The light collimation device includes: a curved reflection member configured to reflect a light from a light source disposed at a focus of the curved reflection member into a light guide member; the light guide member configured to make the light incident into the light guide member propagate by total reflection; and a light extraction structure disposed on the light guide member and configured to extract the light from the light guide member in a collimated manner.