Liquid injection apparatus

A liquid injection apparatus includes a plurality of liquid droplet injectors arranged on a suction pipe of an internal combustion engine and adapted to eject liquid droplets into the suction pipe by pressurizing liquid contained in pressurizing chambers through operation of corresponding piezoelectric/electrostrictive elements. One group of liquid droplet injectors are mounted on the suction pipe in such a manner as to eject liquid droplets into a space located above a horizontal plane including the center axis of the suction pipe. The other group of liquid droplet injectors are mounted on the suction pipe in such a manner as to eject liquid droplets into a space located under the horizontal plane.