An inkjet printhead and a manufacturing method thereof. The inkjet printhead includes a substrate, a substantially cylindrical ink chamber storing ink and formed in an upper portion of the substrate, and a manifold supplying ink to the ink chamber in a bottom portion of the substrate, a channel-forming layer disposed between the ink chamber and the manifold and having an ink channel communicating between the ink chamber and the manifold, a nozzle plate stacked on the substrate and having a nozzle at a location corresponding to the central part of the ink chamber, a heater formed to surround the nozzle of the nozzle plate, and electrodes electrically connected to the heater to supply current to the heater. Therefore, the quantity of ink stored in an ink chamber can be increased. Also, when bubbles grow, the cylindrical ink chamber confines an ink flow area to ink ejectors, thereby reducing a back flow of the ink. Further, the quantity of ink supplied to the ink chamber can be adjusted by varying the number of ink channels formed in the channel-forming layer, thereby improving frequency characteristics of the inkjet printhead.