Country Grammar is the debut studio album by American rapper and singer Nelly. It was released on June 27, 2000, by Universal Records. The production on the album was handled by Jason "Jay E" Epperson, with additional production by C-Love, Kevin Law, City Spud, Steve "Blast" Wills and Basement Beats. Nelly contributed to all lyrics on the album, with Epperson and City Spud also contributing. The album introduced a unique St. Louis sound, and introduces Nelly's vocal style of pop-rap singalongs and Midwestern, Missouri twang. It was supported by four successful singles: "Country Grammar (Hot Shit)", "E.I.", "Ride wit Me" and "Batter Up". Its lead single, "Country Grammar (Hot Shit)", peaked at number 7 on the Billboard Hot 100 and UK Singles Chart. Its second single "E.I." peaked at number 16 on the Hot 100, number 12 on the UK Singles Chart and number 11 on the ARIA Singles Chart. "Ride wit Me" peaked within the top five on the Hot 100, ARIA Singles Chart, Irish Singles Chart and UK Singles Chart. The album's fourth and final single, "Batter Up" featuring St. Lunatics members Murphy Lee and Ali, achieved moderate chart success.

Country Grammar received positive reviews, with critics praising Nelly's vocal style and the album's production. It topped the US Billboard 200 chart for five consecutive weeks, and the US Top R&B/Hip-Hop Albums chart for six consecutive weeks. It peaked in the top five on the New Zealand Albums Chart and Australian Albums Chart, as well as the top ten on the Canadian Albums Chart and Dutch Albums Chart. The album was certified three times platinum by the Recording Industry Association of New Zealand (RIANZ) and Music Canada (MC). The former denoted shipments of 45,000 copies while the latter denoted 300,000 copies.

In 2016, Country Grammar became the ninth hip hop album to be certified Diamond by the Recording Industry Association of America (RIAA), denoting shipment of 10 million copies in the US. Its commercial success secured Nelly's status as one of the most successful hip hop acts of the 2000s decade. On Billboard's decade-end chart, Nelly ranked as the third most successful act of the 2000s decade, due largely to the success of Country Grammar and his follow-up album Nellyville (2002).