Lankapatuna Samudragiri Viharaya (Sinhala: ලංකාපටුන සමුද්‍රගිරි විහාරය) is a Buddhist temple situated in the Trincomalee District, Eastern province of Sri Lanka. This temple which is situated near the ocean near the historic Port of Lankapatuna where Prince Dantha and Princess Hemamala set foot in Sri Lanka bringing the Sacred Tooth Relic of the Buddha. The ruins of the ancient Temple has been heavily damaged by the civil war and tsunami but ruins of an ancient Dageba, Korawak Gal (a type of ancient balustrades), a pond and other ruins of the ancient temple scattered around an area of 50 acres are still visible but a new Temple complex has been built near the ancient Temple's ruins.