Tejano music (Spanish: música tejana), also known as Tex-Mex music, is a popular music style fusing Mexican influences. Its evolution began in northern Mexico (a variation of regional Mexican music known as norteño).

It reached a larger audience in the late 20th century with the popularity of Mazz, Selena, and other performers like La Mafia, Ram Herrera, La Sombra, Elida Reyna, Elsa García, Laura Canales, Intocable, Jay Perez, Emilio Navaira, Esteban "Steve" Jordan, Shelly Lares, David Lee Garza, Jennifer Peña and La Fiebre.

The origins come from the tribe of Chickasaw, when they crossed from Mexico to the United States to Mississippi and among other American cities. Central to the evolution of early Tejano music was the blend of traditional forms such as the corrido and mariachi, and Continental European styles, such as polka introduced by German, Polish, and Czech settlers in the late 19th century. In particular, the accordion was adopted by Tejano folk musicians at the turn of the 20th century, and it became a popular instrument for amateur musicians in Texas and Northern Mexico. Small bands known as orquestas, featuring amateur musicians, became a staple at community dances. Early inceptions of Tejano music demonstrated musical innovation, but also a social and cultural innovation in themes that countered narratives of dominant culture.

At the turn of the century, Tejanos were mostly involved in ranching and agriculture. The only diversion was the occasional traveling musician who would come to the ranches and farms. Their basic instruments were the flute, guitar, and drum, and they sang songs that were passed down through the generations from songs originally sung in Mexico. One of these musicians was Lydia Mendoza, who became one of the first to record Spanish language music as part of RCA's expansion of their popular race records of the 1920s. As these traveling musicians traveled into areas where the German Texans and other European settlers lived.

Norteño/conjunto accordion pioneer Narciso Martínez, known as the "Father of Conjunto Music", defined the accordion's role in conjunto music. He learned many tunes from German, Polish and Czech brass bands and transposed them to accordion. Martínez gave accordion playing a new virtuosity in the 1930s, when he adopted the two button row accordion. At the same time, he formed a group with bajo sexto player Santiago Almeida.

With the accordion, drums, and bajo sexto, Tejanos now had a sound they could begin to call their own. In the 1940s, Valerio Longoria introduced lyrics to conjunto music, further establishing the Tejano claim to this new sound.

In the 1950s, Isidro Lopez further revolutionized the Tejano sound by emphasizing less on the traditional Spanish that Valerio used and using the new Tex-Mex instead. This created a newer sound and took us one step close to the sound we have today. In the 1960s and 70s Little Joe and The Latinaires (later renamed La Familia), The Latin Breed, Luis Ramirez Y su Latin Express, and others infused the orchestra sound into the Tejano sound, taking their influences from Pop, R&B, and other forms of music. In the late 70s and early 80s, there was a new sound emerging with up-and-coming groups like McAllen's Espejismo, led by songwriter/lead singer Rudy Valdez, and Brownsville natives Joe Lopez, Jimmy Gonzalez, and Mazz introduced keyboard to Tejano, influenced by the disco sound of the era. During that period, La Mafia became the first Tejano band to put on rock-style shows for their generation.

Tejano musicians like Flaco Jiménez and Esteban Steve Jordan carried on Martinez's tradition of accordion virtuosity and became a fixture on the international World Music scene by the 1980s.^{[citation needed]}