The present invention relates to the field of plant illumination technologyand specificallyprovides a plant illumination optical device which includes two LED lampbodies. Each of theLED lamp bodies includes a reflector and an LED lamp located at an inner sideof the reflector,and an angle between the central light rays of the two LED lamp bodies isadjustable. The presentinvention further provides a plant cultivation device containing the plantillumination opticaldevice. The plant illurnination optical device and the plant cultivationdevice provided by thepresent invention can reflect the light beyond the planting area to theplanting area and cansupplement the illumination on both sides of the illumination centerline,thereby avoiding lightwaste, improving energy efficiency, improving the illumination uniformity inthe planting area,and improving planting quality of the planting area.
