The club was created from an application by
Unión de Curtidores which merged with Selección de Guanajuato. With the money raised, the directive hired Marcial Ortiz, Raúl Varela, Alfonso Montemayor, Salvador Ramírez, Conrado Muñiz, Vicente Serrano, Pepe Cortes, "Sticks" Ramírez, Elpidio Sánchez, and Joaquín Source Duillo Dobles. It participated in the Liga Mayor's second season (1944–45). The team comprised
Argentine players and Miguel Rugilo that served as coach and goalkeeper holder. Battaglia played defense plus two fronts; Marcos Aurelio scored 14 goals with Ángel Fernández. The team debuted at the Patria stadium on August 20, 1944, against
Atlante and lost by a score of 5–3. In the 1945–46 season, another team appeared in the city: the San Sebastián de León. They placed fourth out of 16 teams with 30 games, 17 wins, 4 draws, 9 losses for 38 points. Their top scorer, with 24 goals, Alberto Mendoza. In the 1946–47 season notable players joined, one of whom was Adalberto López, who scored 33 goals. In general, the team had a great campaign being runner-up with 41 points and maintained a fourteen-game winning streak. Another important element was Marcos Aurelio, who highlighted with 16 goals. A match against Atlante was scheduled place in
Mexico City on June 1, 1947, in the Estadio Insurgentes (now
Estadio Ciudad de los Deportes) which took place in León, but had to switch venues due to an epidemic of
foot-and-mouth disease afflicting the Bajío region In a match against
América on May 9, 1946, Florencio Caffaratti accidentally touched an electrical wire after scoring a goal. Alfonso Montemayor rescued him. Subsequently, Caffaratti gave a gold coin to Montemayor with the inscription: "In appreciation of Montemayor by F. Caffaratti."
1947–48 When José María Casullo coached Club León, the greens lost seven times, three of them against
Atlas. The team tied at 36 points with the Jalisco Gold at first place. Jalisco Gold broke the tie with a score of 2–0.
1948–49 Club León defeated
Asturias 2–0 with goals by Adalberto López to prevent a tie with
Atlas and
Guadalajara who remained a point, and Leon became the first to win the tournament campeonísimo cup after defeating
Atlante 3–0 on August 14, 1949.
1951–52 Club León switched coaches to Antonio López Herranz. Antonio Carbajal joined the team with the return of Marcos Aurelio, Sergio Bravo, and Saturnino Martínez. The team played against a Guadalajara team coached by José María Casullo. León won both games of the year with scores of 1–0. In the penultimate round, León lost to Guadalajara by 1 point. In the following season, the team remained in third place at 27 points. For the 1953–54, season it finished in eighth place with 21 points.
1955–56 The season's roster increased to 14 teams. León won the best streak in club history with 12 wins and 7 draws before losing against
Tampico (1–0). The final game was played at the
Estadio Olímpico in Mexico City, where León defeated Oro (4–2) and
Toluca. In 1956–57, León lost to Guadalajara. In 1957–58, they reached fifth place but won the
Copa MX title.
1960s León remained in fifth place in the 1960–61 season with 26 points, fifth place in the 1961–62 season with 25 points, ninth place in the 1962–63 season with 25 points, ninth place in the 1963–64 season with 25 points, seventh place in the 1964–65 season with 30 points, ninth place in the 1965–66 season with 28 points, fifth place in the 1966–67 season with 34 points, fifth place in the 1967–68 season with 35 points, seventh place in the 1968–69 season with 31 points, and seventh place in the 1969–70 season with 31 points.
1970s For the
Mexico 1970 World Cup, there were two technical changes: the starter Argentine Luis Grill was replaced, but was reinstated after
Antonio Carbajal left, as a result, left with 33 points to fourth overall Sergio Anaya new stand becomes scorer the contest with 16 touchdowns, while Luis Estrada scored 13 goals. 1970–71 players arrive,
Jorge Davino, Roberto Salomone and Juan José Valiente who scored ten goals, the club was led by Carbajal and ranked fourth with 38 points. In 1972–73, Antonio Carbajal was replaced by
Rafael Albrecht who served as player and coach. The final game was against
Cruz Azul. In 1973–74, the team failed to qualify at fifth place with 40 points.
First relegation In 1986–87, Jorge Davino scored 10 points in 19 days and León was subsequently relegated to the
Segunda División de México. However, they would reappear in the
Primera División de México on May 10, 2012 and won the Apertura 2012 when they arrived back to the Primera División.
1990s The
Esmeraldas returned to the Primera División for the 1990–91 season and were coached by Víctor Manuel Vucetich, who debuted in the top flight and led the entire tournament. He led the club in sixth place with 41 points, but did not qualify to be third in group 3, and Martin Uribe and Francisco Peña highlighted with 13 and 12 goals.
Second relegation Robert Zermeño cost the team and landed them in last place with 19 points. After the second relegation, the club was sold to Argentine businessman Carlos Ahumada. On November 19, 2010,
Grupo Pachuca purchased the club.
Return to Primera División Argentine
Gustavo Matosas began leading León on January 7, 2012, after being hired in September 2011. During the Apertura 2011 tournament, he could not have a presence off the bench or be registered as coach because he had coached
Querétaro in the same tournament. Matosas' team received 10 wins, 4 draws, and 0 defeats in 14 regular season fixtures, resulted in an ERA of 70.83% and the overall leader, helping them earn a direct qualification to semi-finals of the play-offs. In the semi-finals, they faced
Correcaminos UAT and won 1–0 in the second match before facing
Lobos BUAP in the final, winning by an aggregate score of 7–3 and the right to play again in the
Promotional Final. Facing the
2011 Apertura championship winners Correcaminos UAT, León won by an aggregate score of 6–2, thus returning to the Mexican top-flight for the
2012–13 season. León had struggled for their fourth final for promotion after losing against
Irapuato in 2003,
Dorados de Sinaloa in 2005, and
Indios de Ciudad Juárez in 2008. León won both tournaments (the Apertura and Clausura) of the
2013–14 season and became the first team in Mexico's history to win two consecutive championship titles twice — winning the first of these during the
1947–48 and
1948–49 leagues consecutively. Matosas and León parted ways after failing to make it to the Apertura 2014 championship stage. Argentine
Juan Antonio Pizzi was named as his replacement. On January 31, 2016, following a 3–1 away loss to
Tigres UANL, Pizzi left the charge to join
Chile as their new manager and was subsequently replaced by
Luis Fernando Tena. The club managed to reach the semi-final stage of the
Clausura 2016 championship, losing out to sibling club and eventual winners
Pachuca with an aggregate score of 3–2. Following a lackluster beginning to the
Apertura 2016 where León summed up 4 points within 7 league matches, Tena was let go and Argentine
Javier Torrente was brought in. Regardless of the uninspiring start, the club managed to reach the
Apertura 2016 championship stage, losing to eventual winners
Tigres UANL in the semi-finals by an aggregate score of 3–1. In August 2017, Torrente was let go after a year as manager and was replaced by
Gustavo Díaz. On September 18, 2018,
Ignacio Ambríz was named manager of León, replacing Díaz. During the
Clausura 2019 tournament, he helped León attain the records of most consecutive wins with eleven points, and the most points ever attained during the 17-match tournament format (41 points). They faced Tigres UANL in the
Clausura 2019 championship final, but lost following an aggregate score of 1–0. Regardless, Ambríz's feats with the club contributed to him being named best manager at the conclusion of the
season. After a first place finish with 40 points in the
Guardianes 2020 general table, on December 13, León won the league title defeating
Club Universidad Nacional with an aggregate score of
3–1, becoming Mexico's joint fourth most successful team with eight titles in total alongside
Cruz Azul. After winning the
2023 CONCACAF Champions League, the club was initially qualified to the upcoming
2025 FIFA Club World Cup, for being one of the four winners of the
CONCACAF Champions League between 2021 and 2024. However, on March 21, 2025, Club León was disqualified from the upcoming
2025 FIFA Club World Cup after
FIFA ruled that the club had failed to meet tournament regulations on multi-club ownership regarding its connections to Grupo Pachuca, which also owns
Pachuca, eventually being replaced by
Los Angeles F.C. ==León Stadium==