At the time of the attack on Pearl Harbor, "Amagiri" was assigned to Destroyer Division 20 of Desron 3 of the IJN 1st Fleet, and had deployed from Kure Naval District to the port of Samah on Hainan Island. From 4 December 1941, to the end of the year, "Amagiri" covered the landings of Japanese troops in Malaya, and was part of the escort in support of "Operation L" (the invasion of Banka and Palembang in the Netherlands East Indies. At the end of February, "Amagiri" covered minesweeping operations around Singapore and Johore. In March, "Amagiri" was assigned to "Operation T" (the invasion of northern Sumatra) and "Operation D" (the invasion of the Andaman Islands). During the Indian Ocean raids, "Amagiri" — together with the heavy cruisers and sank the British passenger ship "Dardanus", Steamship "Gandara" and Merchant ship "Indora". From 13–22 April, "Amagiri" returned via Singapore and Camranh Bay to Kure Naval Arsenal, for maintenance.