Long-span installation of optical cables is realizable by virtue of their light weight, small outer diameter, lower transmission line loss due to reduction of the number of splices, effective installation operations, etc. The authors have developed a novel long-span installation machine for optical cables and a practical method of installation using this machine. The machine is found to be applicable in practice based on its fundamental composition of a pair of upper and lower caterpillars and a drive motor. The machine is distinguished by the following performance characteristics and functions: (i) it can pull cables of different OD and a pulling rope with a constant speed; (ii) the maximum pulling load is 300 kgf; (iii) the small, light-weight equipment can be installed in any kind of manhole; (iv) the equipment can be operated by a utility power supply or portable generator; (v) there are control provisions for pulling force limitation and cable slack detection to facilitate automatic cable installation. Another advantage is the “distributed pull system,” wherein the pulling force needed for cable installation is distributively loaded over the cable length. In combination with these features, 14 optical cable sections were actually installed in a duct section of 18 km length. The average section length was 1,300 m and the maximum was as long as 2,500 m. As a result, the practical applicability of the above equipment was proved, showing that they satisfy the design criteria and functions and that there is no significant increase in cable losses after the installation operations.