The Canadian Broadcast Standards Council said Schlessinger, known as Dr. Laura, violated the human rights provision of the Canadian Association of Broadcasters' code of ethics.
The decision, announced Wednesday, means Canadian networks that broadcast the syndicated show must make a public announcement about the council ruling during prime-time hours. Her program is believed to reach almost one million Canadians. There is no further penalty on the show.
Schlessinger has about 15 million listeners weekly on more than 400 stations in the United States. She also writes a column that appears in more than 100 newspapers.
Known for her socially conservative opinions and combative style, she offers advice to listeners on relationships and other matters. Gay rights groups have protested the program in the United States, including a rally in March outside the Paramount Pictures lot in Los Angeles against the studio's plans for a television talk show hosted by Schlessinger.
Schlessinger has said she doesn't hate gays, but that homosexual activity runs counter to her religious beliefs. She was not immediately available for reaction to the board ruling.
The Canadian council cited Dr. Laura for characterizing the sexual behavior of gays and lesbians as "abnormal,'' "aberrant,'' "deviant,'' "disordered,'' "dysfunctional'' and "an error.''
"To use such brutal language as she does about such an essential characteristic flies in the face of Canadian provisions relating to human rights," the council decision said.
The council also ruled Schlessinger's generalizations that pedophilia was more prevalent among members of the gay community than the heterosexual community were abusively discriminatory.
It noted Schlessinger lacked a medical degree to practice psychiatry or psychology, and said her views "were more than a quarter of a century out of date in the opinion of the professional psychiatric and psychological associations."
The council is an independent, not-for-profit organization established by the Canadian Association of Broadcasters. It previously has cited radio star Howard Stern for inappropriate comments.
"In Canada, we respect freedom of speech but do not worship it," the council ruling stated.