An aquarium lamp bracket assembly includes a bracket (10100) including a base frame (11110), a coupling tube (12120) located at the front side of the base frame (11110) and defining an axial coupling hole (13130) and a longitudinal opening (14140) and a clamping member (16160) extended from the back side of the base frame (11110) and defining with the elongated base member a clamping mouth (17170) for fastening to a glass panel (91) of an aquarium housing (90), and an adjustable lamp tube holder (20) including a pivot shaft (21) angularly adjustably mounted in the coupling hole (13130) in the coupling tube (12120), a lamp tube holder shell (23) holding a lamp tube (30) and a neck (22) connected between the pivot shaft (21) and the lamp tube holder shell (23) and inserted through the longitudinal opening (14140) of the bracket (10100).
