Ptolemais may refer to:

• Ptolemais of Cyrene, a c. 3rd-century BC mathematician and musical theorist
• Ptolemais, daughter of Ptolemy I Soter and mother of Demetrius the Fair
• Ptolemais (tribe), a phyle of Ancient Athens

• Ptolemais, Cyrenaica, a city in modern-day Libya
• Ptolemais Euergetis, in what is now the Faiyum in Egypt
• Ptolemais Hermiou or Ptolemais in the Thebaid, modern-day El Mansha in the Sohag Governorate of Egypt
• Ptolemais Theron, a city on the African coast of the Red Sea

• Ptolemais or Lebedus, on and around the Kısık Peninsula
• Ptolemaida in West Macedonia, Greece
• Ptolemais (Pamphylia), a coastal town of ancient Pamphylia or of Cilicia
• Ptolemais, a name that may have been given to Larisa (Troad), Anatolia
• Ptolemais in Phoenicia, later Acre, in modern-day Israel

• All pages with titles beginning with Ptolemais
• Ptolemy (disambiguation)
• Ptolemaic Kingdom
• Ptolemaiida, a taxon of extinct wolf-like mammals