Οι 62 ιαπωνικές εταιρείες που συμμετέχουν στα ΠΟΣΕΙΔΩΝΙΑ 2006 είναι (κατά αλφαβητική σειρά):

- Chugoku Marine Paints Ltd (COATINGS, PAINTS)
- CS Techno Inc. (SHIP SPARE PARTS)
- Daihatsu Diesel Mfg. Co., Ltd.
(GENERATING SETS, MONITORING EQUIPMENT, PROPULSION SYSTEMS  
- East West Navigation Ltd (SHIPPING COMPANIES) 
- Franman Far East Liaison Office 
- Fuji Trading Co., Ltd. 
(REPAIR SERVICES, SHIP SPARE PARTS, SHIP SUPPLIERS)
- Fuji Transport Systems Co., Ltd.
- Furuno Electric Co Ltd (ELECTRICAL, ELECTRONICS) 
- Goltens Japan  (REPAIR SERVICES)  
- Hashihama Dockyard Co., Ltd. (REPAIR SERVICES)  
- IHI Amtec Co., Ltd. (SHIPBUILDING, REPAIR YARDS)   
- IHI Engineering, Marine Co., Ltd.
- IHI Marine Co., Ltd. (REPAIR SERVICES, SHIP SPARE PARTS)
- IHI Marine United Inc. (SHIPBUILDING, REPAIR YARDS)   
- Imabari Shipbuilding Co., Ltd. (SHIPBUILDING, REPAIR YARDS)
- Iwagi Zosen Co., Ltd. (SHIPBUILDING, REPAIR YARDS)
- Japan Radio Co., Ltd. (COMMUNICATION AIDS ELECTRICAL, ELECTRONICS NAVIGATION AIDS)
- Japan Ship Exporters' Association
- Japanese Marine Equipment Association (JSMEA)
- JRCS Corporation 
(AUTOMATION, MONITORING EQUIPMENT, REPAIR SERVICES
- JRCS Mfg. Co., Ltd.
- Kawasaki Shipbuilding Corporation (SHIPBUILDING, REPAIR YARDS)
- Koyo Dockyard Co., Ltd (REPAIR SERVICES, SHIPBUILDING, REPAIR YARDS)
- Kyodo (DECK EQUIPMENT, PUMPS, VALVES, SHIP SPARE PARTS) 
- MES Technoservice Co Ltd, Mitsui MAN B&W Turbochargers  (ENGINEROOM EQUIPMENT) 
- Mitsubishi Heavy Industries, Ltd. (SHIPBUILDING, REPAIR YARDS) 
- Mitsubishi Heavy Industries, MET Turbochargers 
(ENGINEROOM EQUIPMENT)  
- Mitsui Engineering & Shipbuilding Co., Ltd. (SHIPBUILDING, REPAIR YARDS)   
- Musasino Co., Ltd. 
- Namura Marine Co., Ltd.
- Namura Shipbuilding Co., Ltd. (SHIPBUILDING, REPAIR YARDS)
- Naniwa Pump Mfg. Co., Ltd. (ENGINEROOM EQUIPMENT, PUMPS, VALVES)
- Nippon Kaiji Kyokai (Class NK) (CLASSIFICATION SOCIETIES)
- Nishi Shipbuilding Co., Ltd. (SHIPBUILDING, REPAIR YARDS)
- Ocean Maritime (ENGINEROOM EQUIPMENT) 
- Ocean Yacht Co., Ltd. (SHIPBUILDING, REPAIR YARDS)
- Oshima Shipbuilding Co., Ltd. (SHIP SUPPLIERS)
- Sanoyas Hishino Meisho Corporation (SHIPBUILDING, REPAIR YARDS)  
- Sasebo Heavy Industries Co. Ltd (SHIPBUILDING, REPAIR YARDS) 
- Shimanami Shipyard Co., Ltd. (SHIPBUILDING, REPAIR YARDS)  
- Shin Kasado Dockyard Co., Ltd. (REPAIR SERVICES) 
- Shin Kasado Shipyard  (REPAIR SERVICES)
- Shin Kurushima Dockyard Co., Ltd. (SHIPBUILDING, REPAIR YARDS) 
- Sumitomo Heavy Industries Marine & Engineering Co., Ltd.  (SHIPBUILDING, REPAIR YARDS) 
- Sunflame Co., Ltd. (ENGINEROOM EQUIPMENT, SHIP SPARE PARTS)
- Taiyo Electric Co., Ltd. (ENGINEROOM EQUIPMENT, SHIP SPARE PARTS) 
- Takashina Life Preservers Co., Ltd. (SAFETY EQUIPMENT, SERVICES)   
- Tanabe Pneumatic Machinery Co., Ltd. (ENGINEROOM EQUIPMENT, SHIP SPARE PARTS)
- The Shipbuilders' Association of Japan 
- Tokimec Inc (DECK EQUIPMENT, NAVIGATION AIDS, SHIP SPARE PARTS)
- Tokyo Nozzle (ENGINEROOM EQUIPMENT)   
- Tsuji Heavy Industries Co., Ltd. (CARGO HANDLING, DECK EQUIPMENT, SHIP SPARE PARTS)
- Tsuji Marine Services Co., Ltd. (REPAIR SERVICES, SHIP SPARE PARTS, CARGO HANDLING, DECK EQUIPMENT)
- Tsuneishi Corporation  (SHIPBUILDING, REPAIR YARDS)
- Tsurumi  (PUMPS, VALVES)
- Universal Marine Supplies Ltd  (CARGO HANDLING, SHIP AGENTS, SHIP SUPPLIERS)
- Universal Shipbuilding Corporation  (SHIPBUILDING, REPAIR YARDS) 
- UZUSHIO ELECTRIC CO., LTD. 
(AUTOMATION, COMPUTER APPLICATIONS, ELECTRICAL, ELECTRONICS, INTERNET SERVICES, MONITORING EQUIPMENT) 
- Yamatake  (AUTOMATION)
- Yanmar Co., Ltd.  (ENGINEROOM EQUIPMENT, PROPULSION SYSTEMS)
- Yanmar Engineering Co., Ltd.  (SAFETY EQUIPMENT, SERVICES, SHIP SPARE PARTS) 
- Yokohama Tsusho Co., Ltd.  (SAFETY EQUIPMENT, SERVICES)