| 321 | | Shipyard of brothers Nobel | Shipbuilding and Ship repair-Shipyard,Shipbuilding and Ship repair-Ship Repair | Russia | B10 |
| 322 | | SIBBIORESURS | Aquaculture-Feeds and Additives | Russia | B19 |
| 323 | | Siberian Invest Group | Aquaculture-Farming | Russia | B17 |
| 324 | | Sigma Marine Technology | Catching and Processing-Catching,Catching and Processing-Processing | Russia | G2 |
| 325 | | SIMBIA ENGINEERING COMPANY, Ltd | Shipbuilding and Ship repair-Ship Equipment and Components | Russia | |
| 326 | | SIRIUS | Product Distribution-Traiding | Russia | J4 |
| 327 | | SK Exclusive | Services-Logistics | Russia | J2 |
| 328 | | Skipskompetanse Rus | Shipbuilding and Ship repair-Engineering Bureau | Norway | D9 |
| 329 | | Skolkovo Foundation | Other-State Institutions | Russia | C18-1 |
| 330 | | Slavtrans-Service | Services-Logistics | Russia | B5 |
| 331 | | Smart Hygiene | Aquaculture-Farming,Aquaculture-Feeds and Additives | Russia | C18-1 |
| 332 |  | SOFIA-CRIMEA | Aquaculture-Farming | Russia | D36 |
| 333 | | Soling Seafood | Catching and Processing-Catching,Catching and Processing-Processing,Product Distribution-Traiding | Russia | H20 |
| 334 | | Souz-Polimer, PTK | Special Equipment-Packaging | Russia | D5 |
| 335 | | Sovcombank | Services-Financial and Insurance services | Russia | J9 |
| 336 | | Specialized Transport Logistics Company | Services-Logistics | Russia | B5 |
| 337 | | SPK "Kryimskyikh Partizan" (TM Ellas) | Aquaculture-Farming | Russia | D36 |
| 338 | | Strazh, IPK | Services-Logistics | Russia | B5 |
| 339 | | STT Marine Service | Shipbuilding and Ship repair-Ship Systems,Shipbuilding and Ship repair-Ship Equipment and Components,Shipbuilding and Ship repair-Engineering Bureau | Russia | E12 |
| 340 | | Sydorybtechmash | Catching and Processing-Processing,Shipbuilding and Ship repair-Engineering Bureau | Russia | F13 |
