Akiko made her first song debut in 1965 with "Blue Fallen Leaves" (青い落葉, "Aoi rakuyō"). Her most famous song would be Rainbow Lake (虹色の湖, "Nijiiro no mizūmi") in 1967. During the heyday of Group Sounds, she sold 800,000 copies as a female solo singer. This song became her biggest hit and climbed up to number three on the chart. At that time, she dressed her style from miniskirts to military uniforms. Her next 1968 single "Sand Cross" (砂の十字架, "Suna no jūjika") was also became a success.