The only submarine of her class to be completed, she was commissioned in late January 1945 and was sunk on the return leg of her second voyage in July 1945.

[1] She was assigned to Submarine Division 15 in the 6th Fleet on 4 April 1945, and continued training in the Seto Inland Sea until mid-April.

[1] On 1 May 1945, I-351 departed Kure bound for Singapore on her first transport mission, carrying a cargo of aircraft parts, ammunition, and clothing.

[1] On 18 May 1945, Fleet Radio Unit, Melbourne (FRUMEL), an Allied signals intelligence unit in Melbourne, Australia, reported that it had decrypted a message reporting I-351′s arrival at Singapore, that she had entered drydock on 17 May 1945, and that she planned to change ballast, leave drydock on 20 May, load a cargo of aviation gasoline, and depart Singapore on 21 May.

[1] She actually got underway for Singapore at 14:00 on 22 June, carrying 60 boxes of code books for the 10th Area Fleet and personnel slated to command the submarines I-501 and I-502.

[1] Allied Ultra intelligence accurately reported her departure that day, adding that she might be off the coast of China at 28 degrees 20 minutes North at 12:00 on 25 June 1945.

[1] At 17:45 on 26 June, the United States Navy submarine USS Dentuda (SS-335), under the command of Lieutenant Commander John S. McCain Jr., detected high-speed screws at the northern end of the Formosa Strait[2] and at 17:27 identified the vessel by periscope observation as an "I-class submarine" proceeding on the surface at an estimated speed of 16 knots (30 km/h; 18 mph).

[1] They said that one of the torpedoes struck I-351 in her aviation gasoline tank, causing a huge explosion which knocked them unconscious and blew them overboard.

[1] On 31 July 1945, the Imperial Japanese Navy declared I-351 to be presumed lost with all hands in the South China Sea.