"Kaimei Maru" was assigned to Army group 262, which supported the 14th Army troops, comprising elements of the 16th Division and 48th Division taking part in the Invasion of the Philippines. During the invasion, "Kaimei Maru" was one of around 20 Japanese army transports ferrying roughly 7,000 troops under the command of Count Hisaichi Terauchi, Lt. General Masaharu Homma and Maj. General Susumu Morioka for the campaign's operations around Lamon Bay, Luzon in December 1941. The invasion fleet was supported by elements of the Imperial Japanese Navy (IJN) including the IJN Southern Force under Vice Admiral Nobutake Kondō, IJN Philippines Invasion Group under Vice Admiral Ibō Takahashi and specialist forces of the Philippines Invasion Unit, 1st Base Force HQ under Rear Admiral Kyuji Kubo in command of .