Porphyry ( /ˈpɔrfɪri/; Greek: Πορφύριος, porphyrios "purple-clad") may refer to:
- Porphyry (geology), an igneous rock with large crystals in a fine-grained matrix, or associated mineral deposit
- Porphyry copper deposit, a primary (low grade) ore deposit of copper, consisting of porphyry rocks
- Porphyritic, the general igneous texture of a rock with two distinct crystal (phenocryst) sizes
- Porphyry (philosopher) (234 - c. 305), a Neoplatonic philosopher
- Porphyry of Gaza (or "St. Porphyry of Gaza"), Bishop of Gaza c. 347–420
- Porphyry, a vineyard near Seaham, New South Wales
- Porphyry, a system of astrological house division
- Porphyry Island