| Term | Definition / Meaning / Stand for |
| JAFA |
Japan Amateur Football Association |
| JAPAN |
Japan Association for the Promotion of Arts and Nature |
| JAN |
Japan Association of Neurology |
| JCC |
Japan Chamber of Commerce |
| JCCA |
Japan Civil Contractors Association |
| JCEIA |
Japan Clean Energy Industry Association |
| JCU |
Japan Conservation Union |
| JCBA |
Japan Construction Business Association |
| JCPA |
Japan Consumer Protection Agency |
| JCL |
Japan Corporate Law Association |
| JCA |
Japan Crafts Association |
| JEC |
Japan Economic Council |
| JFBA |
Japan Federation of Bar Associations |
| JFM |
Japan Fisheries Management Association |
| JFC |
Japan Foundation Center |
| JGA |
Japan Golf Association |
| JGC |
Japan Green Council |
| JHF |
Japan Housing Federation |
| JIDC |
Japan Industrial Design Council |
| JIF |
Japan Innovation Foundation |
| JITCO |
Japan International Training Cooperation Organization |
| JMAR |
Japan Maritime Association and Registry |
| JMSA |
Japan Medical Science Association |
| JMEA |
Japan Music Educators Association |
| JNA |
Japan Nursing Association |
| JOPA |
Japan Ophthalmology Practitioners Association |
| JOS |
Japan Ornithological Society |
| JPS |
Japan Pediatric Society |
| JPA |
Japan Pharmaceutical Association |
| JPTA |
Japan Physical Therapy Association |
| JPUB |
Japan Public Utilities Board |
| JQA |
Japan Quality Assurance Organization |
| JSEC |
Japan Securities Exchange Council |
| JSBA |
Japan Snowboarding Association |
| JSCM |
Japan Society for Clinical Microbiology |
| JSD |
Japan Society for Design |
| JSHS |
Japan Society for High School Science |
| JSPF |
Japan Society for Plasma and Fusion Research |
| JSES |
Japan Society of Environmental Sciences |
| JSN |
Japan Society of Neurology |
| JSOT |
Japan Society of Occupational Therapy |
| JSPE |
Japan Society of Power Engineering |
| JSA |
Japan Standards Association |
| JTS |
Japan Telecommunications Society |
| JTL |
Japan Tourism League |
| JUA |
Japan Urban Association |
| JUS |
Japan Utility Society |
| JWSS |
Japan Water Supply System |
| JWNA |
Japan Water and Nature Association |
| JWS |
Japan Wind Society |
| JWHC |
Japan World Heritage Committee |
| JYP |
Japan Young Professionals |
| JACC |
Japan-America Chamber of Commerce |
| JAMDAT |
Japanese American Medical Data and Technology |
| JASA |
Japanese American Service Association |
| JBJA |
Japanese Baseball Journalists Association |
| JTPA |
Japanese Technology Professionals Association |
| JAWS |
Journalists Association of Western States |
| JAI |
Justice and Accountability Initiative |
| JDC |
American Jewish Joint Distribution Committee |
| JSP |
Jack Straw Productions |
| JITO |
Jain International Trade Organisation |
| JAD |
Jamaah Ansharut Daulah |
| JCIA |
Jamaica Castor Industry Association |
| JOTA |
Jamboree of the Air |
| JOTA |
Jamboree on the Air |
| JASNA |
Jane Austen Society of North America |
| JAMMA |
Japan Amusement Machine and Marketing Association |
| JAEA |
Japan Atomic Energy Agency |
| JAA |
Japan Automobile Association |