Seibu L00 series

Seibu L00 series
L00 series set in March 2026
In service	2026–present
Manufacturer	Mitsubishi Heavy Industries
Built at	Mihara, Hiroshima[1]
Family name	Leo Liner
Replaced	8500 series
Constructed	2025–present[1]
Entered service	27 March 2026
Number under construction	8 vehicles (2 sets)
Number built	4 vehicles (1 set)
Formation	4 cars per trainset
Capacity	144 (56 seated) per set[1]
Operator	Seibu Railway
Line served	Yamaguchi Line
Specifications
Car body construction	Aluminum alloy
Train length	34,000 mm (111 ft 7 in)
Car length	8,500 mm (27 ft 11 in)
Width	2,420 mm (7 ft 11 in)
Height	3,340 mm (10 ft 11 in)
Doors	1 per side
Maximum speed	60 km/h (37 mph) (design)
Traction system	2-level VVVF
Traction motors	Three-phase induction motor
Acceleration	3.5 km/(h⋅s) (2.2 mph/s)
Deceleration	3.5 km/(h⋅s) (2.2 mph/s) 5 km/(h⋅s) (3.1 mph/s) (emergency)
Electric systems	750 V DC (Third rail)
Notes/references
Specifications:[2]

The Seibu L00 series (西武L00系, Seibu Reo-kei)^[3] is a people mover train type operated by the private railway operator Seibu Railway on Yamaguchi Line services since 2026. Three four-car sets are to be built by Mitsubishi Heavy Industries by fiscal 2027 to replace the ageing 8500 series fleet.^[4]

Exterior

The first set features a livery that is based on the Saitama Seibu Lions.^[1] The second set is expected to receive a navy blue livery with decorations inspired by the fireworks and illuminations at the Seibu-en amusement park.^[4]

Interior

Passenger accommodation consists of mostly longitudinal seating throughout with a bench seat for one child and one adult faces at the front end of each lead car. All cars have an accessible "free space". The intermediate cars feature showcase displays. LCD displays are installed above the doorways.^[2]

Formation

Sets are formed as shown below.^[2]

Designation	Tc1	M1	M2	Tc2
Weight (t)	10.2	10.5	10.4	10.2
Capacity (total/seated)	32/12	40/16	40/16	32/12

History

Details of the new Leo Liner train type on order were first announced on 22 January 2025.^[5]

On 18 November 2025, Seibu announced that the new Leo Liner train type would be classified as the L00 series. The first set was unveiled at the Mitsubishi Heavy Industries Mihara works on that same day and delivered later in that month.^[1][6]

The L00 series entered revenue service on 27 March 2026.^[3] Following that, one set is scheduled to be introduced every year until fiscal 2027.^[1]

References

1. "西武「新型レオライナー」2026年3月デビュー 第1編成が完成 新形式「れおけい」の由来は?" [Seibu's "New Leo Liner" to debut in March 2026, first train completed - what is the origin of the new "Leo-kei" model?]. Traffic News (in Japanese). Japan: Mediavague Co., Ltd. 18 November 2025. Retrieved 12 March 2026.
2. "西武山口線「L00系」新型車両を報道公開、3/27デビュー - 写真75枚" [Seibu Yamaguchi Line new "L00 series" train revealed to press, debuting on 27 March - 75 photos]. Mynavi News (in Japanese). Japan. 11 March 2026. Retrieved 12 March 2026.
3. Fukuoka, Makoto (27 March 2026). 西武山口線レオライナー新型車両「L00系（れおけい）」デビュー [Seibu Yamaguchi Line's new Leo Liner train, the "L00 series (Reo-kei)," makes its debut]. Tetsudo Shimbun (in Japanese). Retrieved 27 March 2026.
4. "西武鉄道「レオライナー」新型車両L00系の第2編成、デザインが決定" [Train design for Seibu Railway's new L00 series "Leo Liner" second train decided]. Mynavi News (in Japanese). Japan: Mynavi Corporation. 5 March 2026. Retrieved 12 March 2026.
5. "西西武鉄道「レオライナー」山口線に新型車両、2025年度末から導入へ" [Seibu Railway to introduce new Yamaguchi Line “Leo Liner” trains from the end of fiscal year 2025]. Mynavi News (in Japanese). Japan: Mynavi Corporation. 22 January 2025. Retrieved 12 March 2026.
6. "新型「レオライナー」西武へ到着! 夜間の搬入シーンの動画が公開 広島の製造元も反応" [New "Leo Liner" arrives at Seibu! Video of nighttime delivery released, Hiroshima manufacturer also responds]. Traffic News (in Japanese). Japan: Mediavague Co., Ltd. 22 November 2025. Retrieved 12 March 2026.