Trimeresurus cantori, also commonly known as Cantor's pit viper or Cantor's pitviper, is a species of venomous pit viper in the subfamily Crotalinae of the family Viperidae. The species is native to the Nicobar Islands and possibly the Andaman Islands of the eastern Indian Ocean. It was named after Theodore Edward Cantor (1809–1860), a Danish naturalist serving as a surgeon with the East India Company in Calcutta. No subspecies are recognized as being valid.