SLA may refer to:

Geography Martín Miguel de Güemes International Airport, Salta, Argentina, IATA code

Science and engineering Sealed lead-acid battery Second-language acquisition Short long arms suspension, in vehicles Soluble liver antigen or O-phosphoseryl-tRNA(Sec) selenium transferase, an enzyme Spacecraft Lunar Module Adapter, part of Apollo/Saturn S-IVB Specific leaf area, ratio of leaf area to dry mass on a plant Stereo lithographic apparatus, a 3D printing technology

Organizations Science Leadership Academy, Philadelphia, Pennsylvania, US School Library Association Sindhi Language Authority, Pakistan Singapore Land Authority Special Libraries Association, for librarians State Liquor Authority, New York, US

Armies Sindhudesh Liberation Army, a separatist organisation in Pakistan South Lebanon Army, Lebanese Civil War militia Sri Lanka Army Sudan Liberation Movement/Army, a rebel group in Darfur Symbionese Liberation Army, 1970s US radical group

Other Service-level agreement SLA Industries, a role-playing game File format used by Scribus software Softwood Lumber Agreement between US and Canada