A lamp shield (1) for coupling to an illuminating device (2) includes a housing (21) and a light source (22) disposed in the housing (21). The lamp shield (1) includes a top wall (11) having a reflecting surface (114) for facing the light source (22), and a surrounding wall (12) connected to the top wall (11). The surrounding wall (12) has a light transmissive portion (121), and an engaging portion (122) respectively proximate to and distal from the top wall (11). The engaging portion (122) has at least one slit (14) extending from a bottom edge (17) thereof toward the light transmissive portion (121), and is for engaging the housing (21). The light transmissive portion (121) includes a plurality of connecting ribs (123) interconnecting the top wall (11) and the engaging portion (121), and a plurality of light-passage holes (124) alternating with the connecting ribs (123).