A modularized servo case includes a hollow first barrel and a hollow second barrel, each of which has a lower opening at a bottom end thereof. The first barrel and the second barrel have a first connecting portion and a second connecting portion disposed on outer surfaces thereof, respectively. The first and second barrels can be combined together by engagement between the first connecting portion and the second connecting portion. In this way, the different inner components required for the first and second barrels can be separately installed beforehand by modularization, and then the first and second barrels can be assembled. Therefore, the assembly is preferably convenient and the inner components can be assembled simultaneously, thus enhancing the whole production capacity and efficiency and facilitating the disassembly procedure in the later repair and maintenance operation.