Siab or SIAB may refer to:
Ship in a bottle, a type of impossible bottle Siab-e Darvish (also Sīāb), a village in Gachi Rural District, Malekshahi County, Ilam Province, Iran Sirab (also Siab), a village and municipality in the Babek Rayon of Nakhchivan, Azerbaijan SIAB: Shell in a Box, Web-based SSH SIAB, a Romanian acronym for the Bucharest International Auto Show SIAB, an abbreviation for the sodium-ion aqueous battery SIAB (company), a former Swedish construction company Svenska Industribyggen AB Schools International Athletic Board, a British organization hosting sport of athletics meetings for young athletes