Abstract: A bundle tube type optical cable is disclosed. A bundle tube type optical cable comprises: a bundle of optical fiber tubes being arranged in the middle portion of the optical cable and each containing at least two optical fiber cores loosely arranged therein; a first water-blocking layer protecting the optical fiber cores in the optical fiber tube from external moisture by a water-blocking material filled in the inner space of the tube; an inner shell made of aluminum material enclosing the bundle of optical fiber tubes with a predetermined gap; a second water-blocking layer protecting the optical fiber tubes from external moisture by the water-blocking material filled in the inner space of the inner shell; and an outer sheath made of plastic material enclosing the outer surface of the inner shell.