| Rank | Country | dual gauge | Railways |
| Jordan | | total: 505 km narrow gauge: 505 km 1.050-m gauge (2006) |
| Kazakhstan | | total: 13,700 km broad gauge: 13,700 km 1.520-m gauge (3,700 km electrified) (2006) |
| Kenya | | total: 2,778 km narrow gauge: 2,778 km 1.000-m gauge (2006) |
| Kiribati | | void |
| Korea, North | | total: 5,235 km standard gauge: 5,235 km 1.435-m gauge (3,500 km electrified) (2006) |
| Korea, South | | total: 3,472 km standard gauge: 3,472 km 1.435-m gauge (1,342 km electrified) (2006) |
| Kosovo | | total: 430 km (2005) |
| Kuwait | | void |
| Kyrgyzstan | | total: 470 km broad gauge: 470 km 1.520-m gauge (2006) |
| Laos | | void |
| Latvia | | total: 2,303 km broad gauge: 2,270 km 1.520-m gauge (257 km electrified) narrow gauge: 33 km 0.750-m gauge (2006) |
| Lebanon | | total: 401 km standard gauge: 319 km 1.435 m narrow gauge: 82 km 1.050 m note: rail system became unusable because of damage done during fighting in the 1980s and in 2006 (2006) |
| Lesotho | | void |
| Liberia | | total: 490 km standard gauge: 345 km 1.435-m gauge narrow gauge: 145 km 1.067-m gauge note: sections of railway are inoperable because of damage suffered during the civil war (2008) |
| Libya | | 0 km note: Libya has announced plans to build seven lines totaling 2,757 km of 1.435-m gauge track (2006) |
| Liechtenstein | | 9 km 1.435-m gauge (electrified) note: belongs to the Austrian Railway System connecting Austria and Switzerland (2006) |
| Lithuania | | total: 1,771 km broad gauge: 1,749 km 1.524-m gauge (122 km electrified) standard gauge: 22 km 1.435-m gauge (2006) |
| Luxembourg | | total: 275 km standard gauge: 275 km 1.435-m gauge (243 km electrified) (2006) |
| Macau | | void |
| Macedonia | | total: 699 km standard gauge: 699 km 1.435-m gauge (223 km electrified) (2006) |
| Madagascar | | total: 854 km narrow gauge: 854 km 1.000-m gauge (2006) |