A camera module comprising: a holder having a through hole formed therein; a first lens unit disposed in the through hole of the holder; a second lens unit disposed in the through hole of the holder; a liquid lens coupled to the holder, the liquid lens being disposed between the first lens unit and the second lens unit, wherein the first lens unit is disposed on the object-side of the liquid lens; a board configured to be electrically connected to the liquid lens; and an image sensor disposed in an optical-axis direction of the liquid lens, the image sensor being mounted on the board, wherein the liquid lens comprises: a conductive liquid and a nonconductive liquid; a first plate including a cavity in which the conductive liquid and the nonconductive liquid are disposed, wherein the cavity comprises a first opening formed toward the first lens unit and a second opening formed toward the second lens unit, a size of the first opening being smaller than a size of the second opening, a second plate disposed above the first plate, the first opening contacting the second plate; and a third plate disposed under the first plate, the second opening contacting the third plate, wherein O2/O1 is greater than 1.1 and less than 1.6, where O1 is the size of the first opening and O2 is the size of the second opening; characterized in that the following condition is met: 1.126 / 0.824 ≤ D / T ≤ 1.028 / 0.658, wherein D is the distance, on an optical axis, between a rear surface of the first lens unit and a front surface of the second lens unit, and T is the thickness of the liquid lens. a holder having a through hole formed therein; a first lens unit disposed in the through hole of the holder; a second lens unit disposed in the through hole of the holder; a liquid lens coupled to the holder, the liquid lens being disposed between the first lens unit and the second lens unit, wherein the first lens unit is disposed on the object-side of the liquid lens; a board configured to be electrically connected to the liquid lens; and an image sensor disposed in an optical-axis direction of the liquid lens, the image sensor being mounted on the board, wherein the liquid lens comprises: a conductive liquid and a nonconductive liquid; a first plate including a cavity in which the conductive liquid and the nonconductive liquid are disposed, wherein the cavity comprises a first opening formed toward the first lens unit and a second opening formed toward the second lens unit, a size of the first opening being smaller than a size of the second opening, a second plate disposed above the first plate, the first opening contacting the second plate; and a third plate disposed under the first plate, the second opening contacting the third plate, wherein O2/O1 is greater than 1.1 and less than 1.6, where O1 is the size of the first opening and O2 is the size of the second opening; characterized in that the following condition is met: 1.126 / 0.824 ≤ D / T ≤ 1.028 / 0.658, wherein D is the distance, on an optical axis, between a rear surface of the first lens unit and a front surface of the second lens unit, and T is the thickness of the liquid lens. a conductive liquid and a nonconductive liquid; a first plate including a cavity in which the conductive liquid and the nonconductive liquid are disposed, wherein the cavity comprises a first opening formed toward the first lens unit and a second opening formed toward the second lens unit, a size of the first opening being smaller than a size of the second opening, a second plate disposed above the first plate, the first opening contacting the second plate; and a third plate disposed under the first plate, the second opening contacting the third plate, wherein O2/O1 is greater than 1.1 and less than 1.6, where O1 is the size of the first opening and O2 is the size of the second opening; characterized in that the following condition is met: 1.126 / 0.824 ≤ D / T ≤ 1.028 / 0.658, wherein D is the distance, on an optical axis, between a rear surface of the first lens unit and a front surface of the second lens unit, and T is the thickness of the liquid lens.