A common print head module that can accommodate either a single-color or multi-color inkjet print head comprises an ink cartridge having an ink output, and an inkjet chip arranged over the ink output. The ink cartridge internally includes ink channels that terminate through a surface of the ink output, wherein two adjacent ink channels are spaced apart by a channel wall. The channel wall has a top surface lower than the surface of the ink output where the ink channels terminate. The ink channels communicate with ink slots of the inkjet chip. When accommodating a single-color print head, the ink flows out through the ink channels over the channel wall. When accommodating a multi-color print head, the ink slots of the inkjet chip have slot walls that are sealed with the channel walls such that inks of different colors can be separately ejected through the ink slots.