CD 온세 로보스 찰추아파

Once Lobos was founded in 1918, in Chalchuapa. Their first match that year – long before the country had a football league or even a football federation – was against Fuerte 22, a club from nearby Santa Ana. The Club came about after the fusion of clubs Esparta and Germania. They played their first international match that same year, travelling about 60 km (37 mi) north to face a team in Jutiapa, Guatemala. Once Lobos played their first official match against UCA in 1923.

For many decades, the team played its home games at Estadio el Progreso, a pitch within earshot of the ancient Tazumal pyramid and its ballcourt from Pre-Columbian times. In December 2002, Once Lobos moved to the Estadio Cesar Hernández, in the outskirts of the city.

Once Lobos made its first ascension to the Primera División de Fútbol de El Salvador (La Primera) on February 7, 1980 at the Óscar Quiteño stadium in the neighboring city of Santa Ana, where they beat UCA in the second and decisive game. During their first full season in La Primera, struggled to fight-off relegation, made more difficult by the league's decision the previous year to relegate two teams at season's end. They finished 9th, staying ahead of Dragón and Platense, to maintain a spot in La Primera for the 1981 season.

In the 1981 Season, the Chalchuapa side won the "Torneo de Copa" by beating the League Champion Atlético Marte by penalties. At the conclusion of the regulation time, the score was tied one all (Once Lobos scorer was W. Barrera at 27‘) and nothing changed in the ensuing 30-minute overtime.

The 1982 season saw the team come under the direction of Dr. Ricardo Mena Laguán. At the end of the regular season, the teams that made it onto the final Serires were Águila, Atlético Marte, Independiente and Once Lobos. In this elimination round, Atlético Marte defeated Once Lobos 2 nil in the first leg and drawing in the second leg. Once Lobos and Águila fought for 3rd and 4th place respectively in a single game played on December 19. Once Lobos emerged victorious by Penalties after the end of regulation the score read 3 all. Once Lobos capitalized on all 5 shots while Águila could only score 4. Thus achieving the best position for the "yuqueros" in their long history. To make this achievement more impressive, Once Lobos did it with only 10 men on the pitch since the 81st minute in regular time, when Mario D. Campos was sent off.

In their last season at the top level in this period, 1983, Once Lobos made it to the final round once again. Still under the direction of Ricardo Mena Laguán. Joined by Independiente, C.D. FAS and C.D. Águila fought the final in a two-round robin elimination; achieving 3rd place once again by defeating Independiente this time in the last game by a score of 2–1.

After a later relegation to the third division, Once Lobos were promoted to the Segunda División in 1995. They were promoted to La Primera in 2004 through a "play-off" game victory against Chalatenango.

In 2018, Once Lobos celebrated their 100th year of existence, receiving a special recognition from the Legislative Assembly of El Salvador as the oldest football club still in existence in the nation.