Kitty Dukakis, the wife of Gov. Michael S. Dukakis, has entered an alcohol treatment program according to a statement issued by the governor Monday that blamed the letdown after his failed presidential campaign.

Mrs. Dukakis, 52, has had a history of addictions and chemical dependency but was never known to be dependent on alcohol until the statement was released Monday afternoon.In July 1987, Mrs. Dukakis announced that she had recovered from a 26-year dependency on diet pills. The governor's wife said she had conquered her addiction to amphetamines, which she hid from her husband, after undergoing treatment at a Minnesota facility in 1982.

Dukakis said his wife entered the Edgehill Newport facility in Newport, R.I., Sunday evening and will stay there for about 30 days.

"Until shortly after election day on Nov. 8, Kitty had never had a problem with alcohol," Dukakis said.

"Unfortunately, a combination of physical exhaustion, the stress of the campaign effort and the post-election letdown all combined to create a situation in which, on a limited number of occasions while at home, she has used alcohol in excessive quantities," the governor said.

Dukakis said Mrs. Dukakis decided to enter the well-known clinic voluntarily and said he and his family supported her decision.

"We know how loved and respected she is both here in the commonwealth and across the nation - and she is grateful for the love and support she has received from so many good and decent people," Dukakis said.

Mrs. Dukakis, who won high marks as a political campaigner during her husband's 1988 presidential effort, has been prominent in the fight to educate youngsters against the perils of drug and alcohol abuse.