Provided is a liquid lens capable of adjusting a focus by using an electrical signal and/or a fluid pressure. The liquid lens includes a container which has a cavity of which the side cross section has a hemispherical shape and contains an insulating liquid droplet and a conductive liquid droplet which are not mixed in the cavity and have the same density, a lower substrate which is combined with a bottom surface of the container to seal a bottom surface of the cavity, and an upper substrate which is combined with a top surface of the container to seal a top surface of the cavity, wherein the container includes an outer wall where the cavity is formed, a first electrode which is formed on an inner side surface of the outer wall and of which the one end is connected to an external power supply, a first insulating film which is laminated a surface of the first electrode and is in contact with the conductive liquid droplet and the insulating liquid droplet, and a second electrode which is laminated on a portion of a surface of the first insulating film and of which the one end is in contact with the conductive liquid droplet and of which the other end is in contact with the external power supply. Accordingly, it is possible to more efficiently adjust a focus by using a small driving voltage by improving a structure of the cavity of the container.