
Armenia sent a delegation to compete at the 1998 Winter Olympics in Nagano, Japan, from 7–22 February 1998. This marked the nation's second appearance at a Winter Olympics as an independent country. The Armenian delegation consisted of seven athletes: four in figure skating, one in freestyle skiing, one in cross-country skiing, and one in alpine skiing.

Australia competed at the 1998 Winter Olympics in Nagano, Japan. A total number of 24 athletes competed, participating in alpine skiing, biathlon, bobsleigh, cross-country skiing, figure skating, freestyle skiing, short track speed skating, and snowboarding, which appeared for the first time at the Olympics. Freestyle skiers Kirstie Marshall and Jacqui Cooper were some of Australia's best gold medal hopes, but both missed the aerials finals. Zali Steggall won Australia's first individual Winter Olympics medal, gaining bronze in slalom.

Azerbaijan competed in the Winter Olympic Games for the first time at the 1998 Winter Olympics in Nagano, Japan.

Belarus competed at the 1998 Winter Olympics in Nagano, Japan.

Belgium sent a delegation to compete at the 1998 Winter Olympics in Nagano, Japan from 7–22 February 1998. The nation was represented by only one athlete, speed skater Bart Veldkamp. He won a bronze medal in the men's 5,000 metres race. With that bronze medal, Belgium finished in joint 22nd place on the medal table.

Bermuda sent a delegation to compete at the 1998 Winter Olympics in Nagano, Japan from 7–22 February 1998. This marked the territory's third appearance at a Winter Olympic Games with their first coming in the 1992 Albertville Games. Bermuda's delegation consisted of a single athlete, the luge competitor Patrick Singleton. In the men's singles, he came in 27th place.

Brazil sent a delegation to compete at the 1998 Winter Olympics in Nagano, Japan from 7–22 February 1998. The delegation consisted of a single athlete Marcelo Apovian, who competed in alpine skiing. Making his second Olympic appearance, he finished his only event, the men's super-G in 37th place, last among those who finished the race.

Canada competed at the 1998 Winter Olympics in Nagano, Japan. Canada has competed at every Winter Olympic Games.

Croatia competed at the 1998 Winter Olympics in Nagano, Japan.

Cyprus sent a delegation to compete at the 1998 Winter Olympics in Nagano, Japan from 7–22 February 1998. This was Cyprus' sixth appearance at a Winter Olympics. Their delegation to Nagano consisted of a single alpine skier, Andreas Vasili. In the men's slalom competition on the penultimate day of the games, he failed to finish his first run and was eliminated.

The Czech Republic competed at the 1998 Winter Olympics in Nagano, Japan. The medal hopes were set on ice hockey team and Kateřina Neumannová in cross-country skiing. The ice hockey team won their first gold medal in history. Kateřina Neumannová was also successful, winning one silver and one bronze medal. The surprise performance for the team was freestyle skier Aleš Valenta who came fourth.

Denmark competed at the 1998 Winter Olympics in Nagano, Japan. The nation won its first ever medal at the Winter Olympic Games, a silver by the women's curling team.

Estonia competed at the 1998 Winter Olympics in Nagano, Japan.

France competed at the 1998 Winter Olympics in Nagano, Japan.

Georgia competed at the 1998 Winter Olympics in Nagano, Japan.

Germany competed at the 1998 Winter Olympics in Nagano, Japan.

The United Kingdom of Great Britain and Northern Ireland competed as Great Britain at the 1998 Winter Olympics in Nagano, Japan.

India competed at the 1998 Winter Olympics in Nagano, Japan. The nation returned to the Winter Games after missing the 1994 Winter Olympics.

Athletes from Iran competed at the 1998 Winter Olympics in Nagano, Japan. It had been 22 years since the previous time that Iran had competed at the Winter Games. One athlete and three officials represented Iran in the 1998 Olympics.

Ireland returned at the 1998 Winter Olympics in Nagano, Japan after they missed in 1994.

Israel competed at the 1998 Winter Olympics in Nagano, Japan.

Jamaica competed at the 1998 Winter Olympics in Nagano, Japan.Devon Harris Michael Morgan Chris Stokes Dudley Stokes Wayne Thomas Winston Watt

Kenya competed in the 1998 Winter Olympics in Nagano, Japan. The country's participation at the Games marked its Winter Olympics debut, although it had competed in the Summer Olympics since 1956. The delegation consisted of a single cross-country skier, Philip Boit. He had been trained as part of a scheme created by American sportswear company Nike, Inc. Although Boit did not win a medal, his efforts received worldwide attention after gold medallist Bjorn Daehlie of Norway waited for him at the finish line as Boit completed the race in difficult conditions in last place.

North Korea competed as the Democratic People's Republic of Korea at the 1998 Winter Olympics in Nagano, Japan.

South Korea, as Republic of Korea, competed at the 1998 Winter Olympics in Nagano, Japan.

Kyrgyzstan competed at the 1998 Winter Olympics in Nagano, Japan. Biathlete Aleksandr Tropnikov was the only competitor for the Asian nation at these Olympics.

Luxembourg sent a delegation to compete at the 1998 Winter Olympics in Nagano, Japan from 7–22 February 1998. This was Luxembourg's sixth appearance at a Winter Olympic Games. The Luxembourgian delegation consisted of a single athlete, figure skater Patrick Schmit. In the men's singles he finished in 29th place.

Moldova competed at the 1998 Winter Olympics in Nagano, Japan.

Athletes from the Netherlands competed at the 1998 Winter Olympics in Nagano, Japan.

New Zealand competed at the 1998 Winter Olympics in Nagano, Japan.

Poland competed at the 1998 Winter Olympics in Nagano, Japan.

Portugal competed at the 1998 Winter Olympics in Nagano, Japan.

South Africa competed at the 1998 Winter Olympics in Nagano, Japan.

Sweden competed at the 1998 Winter Olympics in Nagano, Japan.

Trinidad and Tobago sent a delegation to compete at the 1998 Winter Olympics in Nagano, Japan from 7–22 February 1998. This was the nation's second time appearing at a Winter Olympic Games. The delegation to Nagano consisted of two bobsledders; Gregory Sun and Curtis Harry. In the two-man competition, they finished in 32nd place.

Turkey sent a delegation to compete at the 1998 Winter Olympics in Nagano, Japan from 7–22 February 1998. This was Turkey's 12th time appearing at a Winter Olympic Games. The Turkish delegation to Nagano consisted of a single alpine skier, Arif Alaftargil. In the men's slalom, he finished in 29th place.

The United States competed at the 1998 Winter Olympics in Nagano, Japan. With Salt Lake City as the host of the 2002 Winter Olympics, a cultural segment of the city was shown at the closing ceremony.

Uzbekistan competed at the 1998 Winter Olympics in Nagano, Japan.

Venezuela sent a delegation to compete in the Winter Olympic Games for the first time at the 1998 Winter Olympics in Nagano, Japan from 7–22 February 1998. The delegation consisted of a single luge competitor, Iginia Boccalandro. In the women's singles she came in 28th place out of 29 competitors.

The United States Virgin Islands competed at the 1998 Winter Olympics in Nagano, Japan.

Athletes from the Federal Republic of Yugoslavia competed at the 1998 Winter Olympics in Nagano, Japan. This was the first Olympic appearance of Montenegrin and Serbian athletes under the Flag of the Federal Republic of Yugoslavia. The nation was banned from the 1994 Winter Olympics due to United Nations war sanctions.