A compact dot sight is provided, in which the inner cylinder is eliminated and no structure protrudes from the left and right side walls of a lens barrel. The dot sight includes: a lens barrel; objective lenses fixed to a front opening of the lens barrel; an eyepiece lens fixed to a rear opening of the lens barrel; a light source for projecting a point image from an inside of the lens barrel to the objective lens; a power supply circuit for supplying power to the light source; and a dot adjustment mechanism that has a holder of the light source and can adjust the position of the point image projected on the objective lens by moving the holder vertically and horizontally.