PORT-AU-PRINCE, Haiti (AP) _ President Henri Namphy has appointed the Supreme Court president to the three-man National Governing Council that rules this Caribbean island nation.

Luc D. Hector, 69, was chosen Monday night to replace Jacques A. Francois, 78, who died of cancer Monday morning.

Francois had no portfolio and was thought to be a token civilian in a government controlled by Namphy and another general, Williams Regala, but Hector said Tuesday that he would play an active role.

''I share ... all the responsibilities,'' he said in a telephone interview. ''All three of us together will be taking common decisions.''

He said he had not been told his role in the council or assigned a portfolio, so ''as of today I'm still unemployed.''

Hector became president of the Supreme Court in 1985 under President Jean- Claude Duvalier, who fled the country Feb. 7, 1986.

Namphy has said repeatedly that he will withdraw from political life after a democratically elected government takes power on the second anniverary of Duvalier's fall.

Haitians overwhelmingly approved a new contitution in a referendum March 29 and general elections are planned for November, but no specific date has been announced.

Francois, appointed to the council in March 1986, was a member of the provisional government that took over after Duvalier fled to France.