Liina Tennosaar (born 23 May 1965) is an Estonian stage, film, and television actress.

Liina Tennosaar was born in Tallinn, the daughter of Kalmer Tennosaar and Sirje Tennosaar (née Arbi). She has one full sibling and one half-sibling from her father's second marriage. Her father was a popular Estonian journalist, singer, and television presenter, perhaps best remembered as "Uncle Kalmer" (Estonian: onu Kalmer), the host of the ETV children's television program "Entel-Tentel". Her mother was a stage, film, and television actress.

She attended primary and secondary school in Tallinn, graduating in 1982, then studied acting at the performing arts faculty of the Tallinn State Conservatory (now the Estonian Academy of Music and Theatre), graduating in 1986.

Liina Tennosaar made her television debut at the age of 22 as Mari in the 1983 Soviet-Estonian comedy television feature film "Püha Susanna ehk meistrite kool" directed by Ago-Endrik Kerge. This was followed by the role of Aili Tõru in the 1986 television drama film "Võtmeküsimus" directed by Ago-Endrik Kerge and the role of Mari in the 1987 historical drama television film "Tants aurukatla ümber" directed by Peeter Simm, based on the novel of the same name by Estonian writer Mats Traat. In 2004 she appeared in the television feature film "Taksirengit" directed by Jussi Niilekselä, based on the play by Mihkel Ulman.