Line 18 may refer to:
China Line 18 (Beijing Subway) Line 18 (Chengdu Metro) Line 18 (Chongqing Rail Transit) Line 18 (Guangzhou Metro) Line 18 (Shanghai Metro)
Other countries Line 18 (São Paulo Metro), a proposed line in Brazil Line 18, part of the Green Line (Stockholm Metro), in Sweden Line 18 (Zürich), or Forch Railway, in Switzerland Paris Metro Line 18, an under construction line in France Sinsen Line, Line 18 of the Oslo Tramway, in Norway
See also List of public transport routes numbered 18