The Port of Haydarpaşa, also known as the Port of Haidar Pasha or the Port of Istanbul, is a general cargo seaport, ro-ro and container terminal, situated in Haydarpaşa, Istanbul, Turkey at the southern entrance to the Bosphorus, near Haydarpaşa Station. It is operated by the Turkish State Railways (TCDD) and serves a hinterland which includes the country's most industrialised areas.

Haydarpaşa is a locality within the Kadıköy and Üsküdar districts on the Asian part of Istanbul, Turkey. Haydarpaşa is named after Ottoman Vizier Haydar Pasha. The place, on the coast of Sea of Marmara, borders to Harem in the northwest and Kadıköy in the southeast. It is a historical area with almost solely public buildings. Haydarpaşa is administered by the Mukhtars of Rasımpaşa and Osmanağa parishes.