A liquid ejecting head unit includes a first nozzle group including a plurality of nozzles, a second nozzle group including another plurality of nozzles, a first flow path substrate including a first pressure chamber group including a plurality of first pressure chambers that eject a liquid from the nozzles of the first nozzle group upon being subjected to a pressure, a second flow path substrate including a second pressure chamber group including a plurality of second pressure chambers that eject a liquid from the nozzles of the second nozzle group upon being subjected to a pressure, and a supply substrate including a first liquid supply path through which the liquid is supplied to the first pressure chamber group, and a second liquid supply path through which the liquid is supplied to the second pressure chamber group.