The Eastern Zone was one of the three regional zones of the 1966 Davis Cup.
8 teams entered the Eastern Zone, competing across 2 sub-zones. The winner of each sub-zones would play against each other to determine who would compete in the Inter-Zonal Zone against the winners of the America Zone and Europe Zone.
Japan defeated the Philippines in the Zone A final, and India defeated Ceylon in the Zone B final. In the Inter-Zonal final India defeated Japan and progressed to the Inter-Zonal Zone.