In operation at 762 mm (2 ft 6 in)
Defunct or converted
- Hidaka Takushoku Railway (converted to 1,067 mm (3 ft 6 in) gauge) (operating)
- Jōshin Dentetsu Jōshin Line (converted to 1,067 mm (3 ft 6 in) gauge) (operating)
- Kabe Line (converted to 1,067 mm (3 ft 6 in) gauge) (operating)
- Kintetsu Yunoyama Line (converted to 1,435 mm (4 ft 8+1⁄2 in) gauge) (operating)
- Kiso Forest Railway (defunct)
- Kurama-dera Cable (converted to 800 mm (2 ft 7+1⁄2 in) gauge) (operating)
- Kurihara Den'en Railway Line (converted to 1,067 mm (3 ft 6 in) gauge) (defunct)
- Kururi Line (converted to 1,067 mm (3 ft 6 in) gauge) (operating)
- Nagareyama Line (converted to 1,067 mm (3 ft 6 in) gauge) (operating)
- Ōigawa Railway Ikawa Line (dual gauge lines with 1,067 mm (3 ft 6 in) gauge track previously present) (converted to 1,067 mm (3 ft 6 in) gauge) (operating)
- Okinawa Prefectural Railways (converted to 1,067 mm (3 ft 6 in) gauge) (defunct)
- Ryūgasaki Line (converted to 1,067 mm (3 ft 6 in) gauge) (operating)
- Sakagawa Line (defunct)
- Tobu Kinugawa Line (converted to 1,067 mm (3 ft 6 in) gauge) (operating)
- Tōbu Yaita Line (converted to 1,067 mm (3 ft 6 in) gauge) (defunct)
- Tomakomai Light Railway (converted to 1,067 mm (3 ft 6 in) gauge) (operating)
- Uchiko Line (converted to 1,067 mm (3 ft 6 in) gauge) (operating)