An aluminum extrusion external framework of LCD monitor primarily comprises a front frame cap, a back frame cap, and a sheathing, which are assembled with one another. Several movable laminas are mounted on the inside of the back frame cap, wherein the locking positions of the movable laminas are adjustable. The aluminum extrusion external framework of the LCD monitor is made of aluminum for lightening its weight and conforming to the recycle-based environmental protection so as to facilitate the heat sinking, reduce the production cost, and increase the product lifetime. Besides, the movable laminas are applied to the raised slideways around the inside of the back frame cap so as to be universally suitable for the existing LCD panel having various specifications and dimensions.