Vampyros Lesbos (Spanish: Las Vampiras) is a 1971 erotic horror film written and directed by Jesús Franco (credited as Franco Manera). The film stars Ewa Strömberg as Linda Westinghouse, an American who works in a Turkish legal firm. Westinghouse has a series of erotic dreams that involve a mysterious vampire woman (played by Soledad Miranda, credited as Susann Korda) who seduces her before feeding on her blood. When she travels to an island to settle an inheritance, Linda recognizes a woman as the vampire from her dreams.

The film was shot in 1970 in Turkey. It was a popular success in theaters in Europe on its release and was the first film to have a more psychedelic score for a Franco film and the first to have a prominent lesbian theme. The film's score became popular in the mid-1990s when it was included on the compilation album Vampyros Lesbos: Sexadelic Dance Party, which reached the top ten on the British Alternative charts.

On a remote Turkish island, the beautiful vampire Countess Nadine Carody lures unwary victims with her seductive nightclub act and sets her sights on Linda, a young American woman working in a legal firm in Istanbul. Linda begins dreaming about Nadine and seeks her home on an island. She is interrupted by Memmet, who warns her not to go to the island. Linda follows Memmet to his chamber, where she walks in on him torturing a young woman. She escapes this encounter and proceeds to the island where Linda meets Nadine. The two go swimming, and Nadine notes that the home they are staying at used to belong to Count Dracula. After Linda begins to feel dizzy from drinking wine, Nadine takes her to a room where the two have sex, and Nadine draws blood from Linda's neck. Linda later finds Nadine motionless in a swimming pool and faints.

The next day, Agra appears in mental distress at a hospital, where she claims to have visions of Nadine. She is under Dr. Seward's care, who then treats his new patient, Linda, who does not have any memory of what she encountered with Nadine. At Nadine's home, she appears alive and recounts to her servant Morpho how she became a vampire and her obsession with Linda, who she wishes to become a vampire. Nadine uses her powers to contact Linda to return to her island, where the two drink blood and have sex. On her return to the hospital, Dr. Seward informs Linda that to remove herself from the vampire's curse she must split the vampire's head with an axe or pierce it with a pole.

Memmet then kidnaps Linda, and her boyfriend Omar begins to search for her. Nadine later arrives at the asylum to have Linda return with her, where she meets Dr. Seward. Dr. Seward admits that he only attempted to help Linda to draw Nadine to him so he could become a vampire. Nadine refuses and has Morpho kill him. As Omar searches for Linda, she is told by Memmet that all women, including his wife Agra, who return from the island become insane, which has driven him to kill various women around the island. Linda manages to kill Memmet with a saw and escapes to find Nadine. She finds Nadine at her home near death, desperate for blood to survive. Linda ignores Nadine's plea, bites her neck, and stabs her with a pole through her left eye. Morpho commits suicide, and Linda is found by Omar, who tries to convince her that the whole experience was a dream.

Vampyros Lesbos was filmed in Turkey between 1 June and 10 July 1970. While Franco used several film devices from his previous film, such as long strip club sequences and female protagonists, the lesbian subtext was more prominent in this film than in any of his previous work. The music score also differs from the jazz soundtracks of his previous films with a more psychedelic music-influenced soundtrack. The soundtrack was composed by Manfred Hübler, Siegfried Schwab and Jesús Franco who credited himself under the alias of David Khune. The film went under several titles before being released as Vampyros Lesbos including Das Mal des Vampirs (Evil of the Vampires) and Im Zeichen der Vampire (Mark of the Vampire). Less than a month after finishing production on Vampyros Lesbos, Franco began working on his next film, She Killed in Ecstasy (1971).

Vampyros Lesbos was released on July 15, 1971, in Germany and in Spain in 1973 where it was a popular with audiences in Europe. The film was released on DVD by Synapse Video on 4 January 2000. Image Entertainment released the film on 27 December 2000 on DVD. It was released as a set by Severin Films in 2015 containing a high-definition Blu-ray and a DVD with a Spanish bootleg of the film.

A remake of Vampyros Lesbos directed by Matthew Saliba was released in 2008. The film follows the story of Franco's film.