INKJET HEAD

An inkjet head includes an ejector unit that ejects ink in accordance with a driving signal and a drive substrate unit that outputs the driving signal. The drive substrate unit includes a drive substrate that generates the driving signal, a case that holds the drive substrate, a cooling jacket, and a connection port connected to the cooling jacket. The cooling jacket is arranged between the drive substrate and the inner surface of the case and cools the drive substrate by passing a cooling medium therein. The connection port is formed in the side wall or the top plate of the case. At least part of the connection port is located in the vicinity of the top plate. This configuration achieves downsizing of the entire inkjet head including the ejector unit and the drive substrate unit including the drive substrate, and also suppresses propagation of high-temperature heat generated by the drive substrate to the ejector unit.