A distance measuring apparatus includes a light source unit generating reference light for distance measuring, a light receiving device receiving light reflected from an object to be measured, which has received the reference light, a mirror controlling a path of the reference light, and controlling a path of light, reflected from the object to be measured, toward the light receiving device, and a sensor lens focusing the light reflected from the mirror on the light receiving device. The sensor lens includes a lens portion refracting light, a flange portion provided around the circumference of the lens portion and including a coupling portion for fixing the sensor lens, and a light passing portion formed at the lens portion.