Naagarahaavu (transl. Cobra) is a 1972 Indian Kannada-language film directed by Puttanna Kanagal, based on T. R. Subba Rao's three novels Nagarahavu, Ondu Gandu Eradu Hennu and Sarpa Mathsara, and starring Vishnuvardhan, Aarathi, K. S. Ashwath and Shubha. The supporting cast features Leelavathi, M. Jayashree, M. N. Lakshmi Devi, Ambareesh, Shivaram, Dheerendra Gopal, Lokanath and Vajramuni. The film has a musical score by Vijaya Bhaskar. Cinematography was done by Chittibabu.

The film revolves around the protagonist's relationship with his teacher, Chamayya (K. S. Ashwath). Chamayya, who is childless treats Ramachari (Vishnuvardhan) as his son. He takes it upon himself to guide Ramachari on the right path despite Ramachari's legendary anger. He usually acts as the negotiator between his student and the people who have issues with Ramachari's behaviour. Ramachari is a young man whose anger is his weakness. He is difficult to reason with and has a great deal of pride. Chamayya is the only person who can convince him to do anything. His love interests are Alamelu (Aarathi) and Margaret (Shubha) who play pivotal parts in his life.

The film was released on 29 December 1972 to widespread critical acclaim and was a success at the box office and paved the way for the stardom of Vishnuvardhan, Ambareesh and Aarathi who became leading actors in Kannada cinema. It has developed a cult following over the years. The character roles of Leelavathi, Dheerendra Gopal, Loknath, M. N. Lakshmi Devi were also critically acclaimed. The film won eight Karnataka State Film Awards for Second Best Film, Best Actor, Best Actress, Best Supporting Actor, Best Supporting Actress, Best Story, Best Screenplay and Best Dialogue. The film also won two Filmfare Awards South for Best Film – Kannada and a Special Award for excellent performance. This film was remade in Hindi as Zehreela Insaan, directed by Puttanna Kanagal himself and in Tamil as Raja Nagam and Kode Nagu in Telugu.

The film was re-released in its digitized version on 20 July 2018. This movie was digitalized by Balaji who is the brother of V. Ravichandran and son of N. Veeraswamy, who was the producer.