Noriko Kamachi (蒲池 法子, Kamachi Noriko; born 10 March 1962), known professionally as Seiko Matsuda (松田 聖子, Matsuda Seiko), is a Japanese singer-songwriter, known for being one of the most popular Japanese idols of the 1980s. Since then, she has continued to release new singles and albums, put on annual summer concert tours, and perform in winter dinner shows. She makes frequent appearances in high-profile TV commercials and movies, and on radio. Her alma mater is Chuo University.
Due to her popularity in the 1980s and her long career, she has been dubbed the "Eternal Idol" by the Japanese media. In January 2011, the Japanese music television program Music Station listed her as the 2nd best-selling idol of all time in Japan, with 29,510,000 records sold. She placed behind pop group SMAP and ahead of Akina Nakamori, her biggest rival of the 1980s.
Matsuda once held the record of 25 number-one hits for musicians from 1983 to 2000 (broken by B'z) and for female solo artists (broken by Ayumi Hamasaki in 2010). Matsuda was a performer on the finale of Kouhaku (Red White Music Battle) in 2014, 2015 and 2025, the prestigious NHK New Year's Eve Music show on which she has performed 25 times, as of 2025.
Noriko Kamachi was born on 10 March 1962, in Chikuhō, Mizuma, Fukuoka Prefecture (present-day Arakimachi, Kurume, Fukuoka Prefecture), the eldest daughter of her parents. Her father was a government official at the Ministry of Health and Welfare and her mother was from a family of former village heads from Yame. She is a descendant of Kamachi Akimori of the Kamachi clan, the lords of Yanagawa Castle, who were the most powerful feudal lords in Chikugo Province in the service of the Ōtomo clan during the Sengoku period.
In 1978, Seiko attended the Miss Seventeen contest held by a popular teenage magazine, where she won the top prize. Following this win, she was spotted and scouted by CBS Sony Producer Muneo Wakamatsu. The sixteen-year-old Noriko Kamachi had to choose between the stage names Seiko Arata or Seiko Matsuda, choosing the latter.
In 1979, she started to rise in popularity as a magazine teen idol, and, in the same year, debuted as an actress in all 26 episodes of the television series Odaijini, broadcast by Nippon TV.
In January 1980, Seiko made her debut as a radio personality, appearing weekly for the entire run of the radio program "The Punch Punch Punch," by Nippon Radio.
In April 1980, she made her musical debut with the song "Hadashi no Kisetsu" (lit. "Barefoot Season"). The song was featured in a television commercial for Shiseido's Ekubo, which was broadcast two months before the song's release, in February. During the commercial broadcast, it was assumed that the actress in the commercial was singing the song. Originally, Seiko was supposed to be a commercial actress; however she had a poor audition and was replaced by Yukiko Yamada. The single was an immediate hit with listeners, debuting at No. 12 on the Oricon Weekly charts and selling over 280,000 copies.
In July 1980, Seiko released her second single "Aoi Sangoshou," which served as the musical backing for Glico's ice cream product Yolel. It was her first single to debut in the Top 3 on the Oricon Weekly Charts and has since sold over 600,000 copies. The single was nominated at the 22nd Japan Record Awards in the category of New Artist Award and was rewarded with the special award in the 11th Japan Music Awards along with Toshihiko Tahara. On the yearly Oricon rankings, the singled ranked 15th. In September 1980, Seiko launched her first concert, entitled "First Kiss."
With the popularity of "Aoi Sangoshou," female fans all over the country were inspired by her haircut, which generated great demand at hair salons and became ubiquitous as the Seiko-chan cut. The haircut inspired future acting idols such as Akina Nakamori and Minako Honda.
In August 1980, Seiko released her first studio album Squall, which included the two previous singles and eight newly recorded songs. The single debuted at No. 2 on the Oricon Weekly charts.
In October 1980, Seiko released her third single "Kaze wa Akiro" (lit. "Wind Is Autumn Color"). It became her third television commercial song to be associated with Shideo, this time for the product Ekubo: Milky Fresh. The song became her first single to debut at number one on the Oricon Weekly Charts and sold over 796,000 copies. On the 1980 yearly Oricon rankings, the single ranked 14th and in the 1981 yearly Oricon rankings, it remained in 65th place. The single became one of the first of her 24 consecutive number-one hits in Japan.
In December 1980, she released her second studio album, North Wind, four months after the previous album's release. The album included the single "Kaze wa Akira" along with its B-side track, "Eighteen," and eight newly recorded songs. The album debuted at number one on the Oricon Weekly charts.
At the end of 1980, Seiko made her first appearance on the 21st edition of the New Year's Eve program Kohaku.
In January 1981, she released her fourth single "Cherry Blossom". Unlike the previous singles, it did not receive much promotion. Despite that, it charted at No.1 on the Oricon Weekly Charts and sold over 676,000 copies. On the yearly Oricon rankings, the singled ranked 9th. After the release, Seiko stated in an interview that it was one of her favorite songs of that time.
In April 1981, she released her fifth single "Natsu no Tobira". It became her fourth television commercial song to be associated with Shideo, and the second one to be used in connection with Ekubo's Milky Fresh. The single charted at number one on the Oricon Weekly Charts and sold over 568,000 copies. On the yearly Oricon rankings, the single ranked 14th. During the same month, she launched her first nationwide series of concerts: 81 Seiko Big Concert in Tokyo. Soon after, she launched another concert tour Nice Summer Seiko, which lasted between July and September.
In May 1981, she released her third studio album Silhouette, which included two previously released singles and 8 newly recorded songs. The album debuted in 2nd place on the Oricon Weekly charts.
In July, she released her sixth single "Shiroi Parasol". The single charted in 1st place on the Oricon Weekly Charts and sold over 488,000 copies. On the yearly Oricon rankings, the single ranked in 23rd place. In August, she received her first major role as an actresses in Nogiku no Hana, as well as performing its theme song, "Hana Hitoiro – Nogiku No Sasayaki". The song was released as the B-side of the single "Shiroi Parasol".