The 1989 Davis Cup (also known as the 1989 Davis Cup by NEC for sponsorship purposes) was the 78th edition of the Davis Cup, the most important tournament between national teams in men's tennis. This year's tournament saw the expansion of the previous World Group Relegation Play-offs round into the World Group qualifying round; instead of advancing directly to the World Group, the Zonal Group I winners would now join the World Group first round losers for a chance to compete in the following year's World Group. This year also marked the introduction of the tiebreak, played at 6–6 in all sets except for the final set.
79 teams would enter the competition, 16 in the World Group, 14 in the Americas Zone, 19 in the Asia/Oceania Zone, and 30 in the Europe/Africa Zone. The Bahamas, Bahrain, the Dominican Republic, Kuwait and Jordan made their first appearances in the tournament.
West Germany defeated Sweden in the final, held at the Schleyer-Halle in Stuttgart, West Germany, on 15–17 December, to win their second consecutive Davis Cup title.[1][2]
West Germany vs. Sweden
Date: 20–24 July
The eight losing teams in the World Group first round ties and eight winners of the Zonal Group I final round ties competed in the World Group qualifying round for spots in the 1990 World Group.
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Australia, 
Israel, 
Italy and 
Mexico remain in the World Group in 1990.
Argentina, 
Netherlands, 
New Zealand and .svg/1280px-Flag_of_Switzerland_(Pantone).svg.png){kind=small}
Switzerland are promoted to the World Group in 1990.
Great Britain, 
Hungary, 
Peru and .svg/1280px-Flag_of_South_Korea_(1984%E2%80%931997).svg.png){kind=small}
South Korea remain in Zonal Group I in 1990.
Denmark, 
Indonesia, .svg/1280px-Flag_of_Paraguay_(1988%E2%80%931990).svg.png){kind=small}
Paraguay and 
Soviet Union are relegated to Zonal Group I in 1990. Peru and Argentina advance to World Group qualifying round..svg/1280px-Flag_of_Ecuador_(1900%E2%80%932009).svg.png){kind=small}
Ecuador relegated to Group II in 1990.
Chile promoted to Group I in 1990..svg/1280px-Flag_of_Hong_Kong_(1959%E2%80%931997).svg.png){kind=small}
Hong Kong relegated to Group II in 1990. New Zealand and South Korea advance to World Group qualifying round.
Pakistan promoted to Group I in 1990. Switzerland, Hungary, Great Britain and Netherlands advance to World Group qualifying round..svg/1280px-Flag_of_Belgium_(civil).svg.png){kind=small}
Belgium promoted to Group I in 1990.
Ghana promoted to Group I in 1990.
