A notebook computer includes a data processing unit, and a display unit pivotally connected with one side of the data processing unit. The display unit has a first casing member, a second casing member, and a third casing member. The first casing member is immovably disposed on the third casing member. The second casing member is separably combined upon the first casing member, which includes a plurality of first through slots, second through slots and a plurality of protrusions. The second casing member includes a plurality of first baffles and second baffles. The first casing member and second casing member can be easily combined with or separated from each other.