Promoter James L. Denson said yesterday he has engaged Jose (Pepino) Cuevas to defend his World Boxing Association welterweight title against Angel Sepada on Saturday, Oct. 20, at RFK Stadium in a 15-round match.

Wilfredo Benitez will defend his World Boxing Council welterweight title against Sugar Ray Leonard on Dec. 1 in Las Vegas and, if Leonard wins, Denson plans to match him with the winner of the WBA bout for the undisputed world championship at RFK in 1980.

Cuevas-Espada will be the first world title bout in the District since May 23, 1941, when Joe Louis won by disqualification over Buddy Baer at Griffith Stadium.

Denson, president of the D.C. Chamber of Commerce, also has reserved the D.C. National Guard Armory for the Cuevas-Espada bout in case of rain. The fight will be televised.

Espada, of Puerto Rico, is ranked as the No. 1 contender by the WBA, with Leonard No. 2, Roberto Duran of Panama, the former lightweight champion, No. 3 and unbeaten Tommy Hearns of Detroit, No. 4.

Cuevas, of Mexico, has been described as a "bigger and better Duran," but Cuevas recently had difficulty decisioning Randy Shields of Los Angeles, who was outpointed by Leonard.

Off comparative performances of the leading welterweights, including Carlos Palomino, Leonard has appeared to be the best.

This comparison is expected to attract area fans to judge Cuevas. The bout also will have a special appeal for the Hispanic community in Washington.

Johnny Gant of Washington, another prominent welterweight, and fellow townsman Derrick Holmes, a bantamweight, will be on the card.

Another boxing special is booked at the armory on Oct. 23, when an all-Africa team will oppose an all-United States team.