Australian researchers Barry Marshall and Robin Warren won the medicine prize for pioneering research into stomach ulcers, proving they are caused by bacteria and therefore treatable with antibiotics.
Americans Roy Glauber and John Hall and German Theodor Haensch won the physics prize for ground-breaking work in optics and the nature of light.
Yves Chauvin of France and Americans Robert Grubbs and Richard Schrock won the chemistry prize for breakthroughs that open the way to smarter drugs and environmentally-friendlier plastics.
The economics prize went to Robert Aumann, an Israeli-US citizen, and Thomas Schelling of the US for using game theory to explain conflict resolution.
The winner of the literature prize, Harold Pinter, did not attend the ceremony or the week-long festivities in the Swedish capital because of ill health.
The 75-year-old British playwright was diagnosed with cancer of the oesophagus in December 2002.
His publisher, Stephen Page, accepted the prize on his behalf.
Each Nobel prize consists of a diploma, a gold medal, and a check for 10 million Swedish kronor ($A1.7 million dollars) to be shared if there is more than one laureate.
The ceremony, traditionally held in Stockholm's Concert Hall on the anniversary of the death of Nobel prize founder Alfred Nobel in 1896, was followed by a gala banquet for 1,300 guests at City Hall attended by Sweden's royal family and members of the government.