Naomasa Sakonju was a vice admiral in the Imperial Japanese Navy during World War II and a convicted war criminal.

In March 1944, a force of three Imperial Japanese Navy (IJN) heavy cruisers raided Allied shipping in the Indian Ocean, the codename of this operation was Operation SA No.1. The cruisers departed Japanese-held territory on 1 March with the support of other IJN vessels and aircraft. On 9 March, they encountered and sank the British steamer Behar, with the heavy cruiser Tone picking up over 100 survivors. Fearing detection, the Japanese force subsequently returned to the Netherlands East Indies (NEI), arriving on 16 March. Two days later, most of Behar's crew and passengers were murdered on board Tone. Following the war the commander of the raid, Rear Admiral Naomasa Sakonju, was executed for this war crime and Tone's captain Haruo Mayuzumi was sentenced to seven years imprisonment.