A lamp (200, 400, 600), comprising: a light guide plate (210, 410) having a light incident surface and a light exit surface; a light source (220, 420) disposed adjacent to the light incident surface; a lampshade structure (100, 300, 500) covering the light guide plate (210, 410), wherein the lampshade structure (100, 300, 500) comprises: a body (110, 310, 510) having an inner concave surface (111, 311, 511) and an outer surface (112, 312, 512) opposite to the inner concave surface (111, 311, 511); and a plurality of light guide structures (120, 320, 520) disposed on the inner concave surface (111, 311, 511) or the outer surface (112, 312, 512), wherein each of the light guide structures (120, 320, 520) has a central thickness (T1, T3, T5) and a peripheral thickness (T2, T4, T6), and the central thickness (T1, T3, T5) is less than the peripheral thickness (T2, T4, T6); and a fixing mount (230, 430), wherein the light guide plate (210, 410), the light source (220, 420) and the lampshade structure (100, 300, 500) are disposed on the fixing mount (230, 430), wherein the fixing mount (230, 430) comprises: a first housing (231, 431); a second housing (232, 432) connected to the first housing (231, 431), wherein the second housing (232, 432) forms an accommodating space (231a, 431a) together with the first housing (231, 431), and the light source (220, 420) and a portion of the light guide plate (210, 410) close to the light incident surface are disposed within the accommodating space (231a, 431a); and a support shaft (233, 433) disposed on the first housing (231, 431), wherein the lampshade structure (100, 300, 500) is disposed on the support shaft (233, 433) to cover the light guide plate (210, 410) and is located at a distance from the light guide plate (210, 410). a light guide plate (210, 410) having a light incident surface and a light exit surface; a light source (220, 420) disposed adjacent to the light incident surface; a lampshade structure (100, 300, 500) covering the light guide plate (210, 410), wherein the lampshade structure (100, 300, 500) comprises: a body (110, 310, 510) having an inner concave surface (111, 311, 511) and an outer surface (112, 312, 512) opposite to the inner concave surface (111, 311, 511); and a plurality of light guide structures (120, 320, 520) disposed on the inner concave surface (111, 311, 511) or the outer surface (112, 312, 512), wherein each of the light guide structures (120, 320, 520) has a central thickness (T1, T3, T5) and a peripheral thickness (T2, T4, T6), and the central thickness (T1, T3, T5) is less than the peripheral thickness (T2, T4, T6); and a body (110, 310, 510) having an inner concave surface (111, 311, 511) and an outer surface (112, 312, 512) opposite to the inner concave surface (111, 311, 511); and a plurality of light guide structures (120, 320, 520) disposed on the inner concave surface (111, 311, 511) or the outer surface (112, 312, 512), wherein each of the light guide structures (120, 320, 520) has a central thickness (T1, T3, T5) and a peripheral thickness (T2, T4, T6), and the central thickness (T1, T3, T5) is less than the peripheral thickness (T2, T4, T6); and a fixing mount (230, 430), wherein the light guide plate (210, 410), the light source (220, 420) and the lampshade structure (100, 300, 500) are disposed on the fixing mount (230, 430), wherein the fixing mount (230, 430) comprises: a first housing (231, 431); a second housing (232, 432) connected to the first housing (231, 431), wherein the second housing (232, 432) forms an accommodating space (231a, 431a) together with the first housing (231, 431), and the light source (220, 420) and a portion of the light guide plate (210, 410) close to the light incident surface are disposed within the accommodating space (231a, 431a); and a support shaft (233, 433) disposed on the first housing (231, 431), wherein the lampshade structure (100, 300, 500) is disposed on the support shaft (233, 433) to cover the light guide plate (210, 410) and is located at a distance from the light guide plate (210, 410). a first housing (231, 431); a second housing (232, 432) connected to the first housing (231, 431), wherein the second housing (232, 432) forms an accommodating space (231a, 431a) together with the first housing (231, 431), and the light source (220, 420) and a portion of the light guide plate (210, 410) close to the light incident surface are disposed within the accommodating space (231a, 431a); and a support shaft (233, 433) disposed on the first housing (231, 431), wherein the lampshade structure (100, 300, 500) is disposed on the support shaft (233, 433) to cover the light guide plate (210, 410) and is located at a distance from the light guide plate (210, 410).