The station and its crew are in no danger but the move may be necessary, the mission control said.
A fragment of the Briz-M upper stage, which was used in a failed launch of Russian and Indonesian satellites from the Baikonur space centre in August 2012, will fly by the ISS at 1.16 pm GMT on Wednesday. The upper stage mishap took the satellites into a wrong orbit and later fell into more than 80 pieces of space debris.
The final decision on the space station's move will be made later, the mission control said.
The current ISS expedition comprises Russian cosmonauts Alexander Skvortsov, Oleg Artemyev and Maxim Surayev, NASA astronauts Steven Swanson and Reid Wiseman and European Space Agency (ESA) astronaut Alexander Gerst.