A glass panel unit (1) is provided with a first panel (T1) comprising at least a first glass sheet (10), a second panel (T2) facing the first panel (T1) and comprising at least a second glass sheet (20), a frame body (30) formed in a frame shape corresponding to a peripheral edge part along an edge of the first panel (T1) and a peripheral edge part along an edge of the second panel (T2) and bondedto both peripheral edge parts, and a spacer (40) provided in a vacuum space (50) between the first panel (T1) and the second panel (T2). The spacer (40) includes a polyimide. The polyimide has an absorption edge at which the absorbance thereof decreases in the light absorption spectrum from ultraviolet rays to visible light rays, the absorption edge being 400 nm or less.