A former honors student at the University of the District of Columbia who was deported as an undocumented alien by the United States and then convicted of murder in his native African country of Botswana is to be executed there today, State Department officials said.

An appeal for clemency for 27-year-old Clement Gofhamodimo was turned down by Botswanan President Qwett Masire, State Department officials said.

A Botswanan Embassy spokesman said yesterday he had no official information on the pending execution of Gofhamodimo, who was convicted of the 1978 murder of a Swiss tourist in Botswana and sentenced to death last January.

Meanwhile, a small group of U-D.C. students picketed near the Botswana Embassy yesterday morning, protesting the news of Gofhamodimo's planned execution.

D.C. Del. Walter E. Fauntroy said yesterday he was "gravely distressed at the action Botswana is taking in ending the life of the young man of whose guilt I am not convinced on the basis of information made available to me."

On Thursday, U-D.C. President Robert L. Green made a last-minute appeal to Masire by telegram to "save he life of this brilliant young man by commuting his sentence" when he heard news of the impending execution, U-D.C. officials said.

Fauntroy and Green had made personal appeals on Gofhamodimo's behalf to Masire when he made a state visit to Washington in May. Masire listened carefully, sources said.

In a recent letter to Fauntroy, Masire explained that a clemency appeal was made by the "Committee on the Prerogative for Mercy," implying the decision was not his alone, a Fauntroy aide said.

Botswana, an arid country of 750,000 persons in southern Africa, has a reputation for respecting civil liberties and judicial independence more than most African countries.

Atlanta Mayor Andrew Young sent a telegram to Masire Thursday pleading for him to spare Gofhamodimo's life, an aide said.

The events that have surrounded Gofhamodimo since he was deported by the U.S. Immigration and Naturalization Service in May 1983 have shocked many U-D.C. students and faculty who recall the third-year student as an intelligent, hard-working person.

He had lived illegally in the United States for six years after entering the country on a tourist visa in 1978. Botswana asked for his deportation many times, and in May 1983 he was arrested at his Riverdale home where he lived with his wife and U.S.-born son.

At his murder trial in the Botswana capital of Gaborone, the prosecution built its case mainly on circumstantial evidence indicating that Gofhamodimo was the last person who saw the Swiss tourist alive. The victim's body was never found. No witnesses or murder weapon was presented in court. Gofhamodimo said he knew the tourist, but he has maintained that he is innocent of the crime.