Gunma 1st District (群馬県第1区, Gunma-ken dai-ichi-ku) is a single-member constituency of the Japanese House of Representatives, the lower house of the National Diet. It is located in Gunma Prefecture and consists of the cities of Maebashi and Numata and the district of Tone as well as parts of the cities of Kiryū, Shibukawa and Midori. As of 2012, 387,120 eligible voters were registered in the district.^[2]

Until 2009, Gunma had been a traditional "conservative kingdom" (hoshu-ōkoku), the Japanese equivalent of a "red state" in the United States. Like all single member districts in Gunma, the 1st district had been represented by the Liberal Democratic Party (LDP) since 1997. The LDP used the Costa Rica method (kosutarika-hōshiki) with Koji Omi and Genichiro Sata as alternating candidates for the district. In the election of 2009, Omi was the LDP's candidate; incumbent Sata only ran in the Northern Kantō proportional representation block. Both Omi and Sata had represented the pre-reform three-member 1st district of Gunma. The Democratic Party's candidate in 2009 was Takeshi Miyazaki, a former journalist for the Jōmō Shimbun.^[3] In 2012, Sata regained the district for the LDP. In 2013, the weekly magazine Shukan Shincho accused Sata of inappropriate sexual conduct.^[4] In the 2014 elections, Sata lost considerable support and did not receive endorsement from Komeito, but still managed to hold onto his seat.

Between 2017 and 2021, the representative was Asako Omi, the daughter of previous representative Kōji Omi. In 2021, the district was won by Yasutaka Nakasone, son of former Foreign Minister Hirofumi Nakasone and grandson of Yasuhiro Nakasone, who was Prime Minister from 1982 to 1987.