PURPOSE: To provide a TTL finder system, which enables designing the whole camera construction in small size and with small wall thickness using a plurality of mirrors wherein the light flux having passed through a photographing lens is set properly.

CONSTITUTION: The light flux having passed through a photographing lens 2 is reflected in the direction perpendicular to the optical axis by No.1 mirror 3 rotatable, reflected in the direction parallel with the optical axis by No.2 mirror 7, reflected in the direction perpendicular to the optical axis by a No.3 mirror 9 upon allowing it to pass behind a photo-sensitive part 13 on which an object image is formed by the photographing lens, and reflected in the direction parallel with the optical axis by a No.4 mirror 11, and then it is led to an eyepiece lens 12. Through this lens 12, it is possible to observe the object image formed by the photographing lens.