Kalju Orro was born in Tartu, where he attended primary and secondary schools. He is a 1970 graduate of Tartu 17 Vocational School. Afterward, he enrolled in the Vanemuine Drama Studios in Tartu, graduating in 1971. In 1972, he enrolled in the Performing Arts Department of Tallinn State Conservatory under instruction of actor and theatre pedagogue Voldemar Panso, graduating in 1976. Among his graduating classmates were Merle Karusoo, Ago-Endrik Kerge, Urmas Kibuspuu, Aare Laanemets, Anne Paluver, Külliki Tool, Priit Pedajas, Eero Spriit, and Peeter Volkonski.
Kalju Orro's first prominent feature-film role was as Markar in the 1977 Peeter Simm, Toomas Tahvel, and Peeter Urbla-directed romantic drama Karikakramäng for Tallinnfilm. Other notable film roles include that of Volt in the 1992 Lembit Ulfsak-directed comedy family filmLammas all paremas nurgas, author August Kitzberg in the Rainer Sarnet-directed 2005 thriller Libahundi needus, and as Uugu in the Elmo Nüganen-directed 2006 comedy Meeletu, which was based on the play of the same name by Jaan Tätte. In 2017, he made a cameo appearance as a hospital patient in the Andres Puustusmaa-directed comedy Rohelised kassid. Orro's first prominent role on Estonian television was as Kilian in the 1976 Elvi Koppel-directed family film Kuidas kuningas kuu peale kippus. Other notable television roles were as Karl in the 1984 Ago-Endrik Kerge-directed and Enn Vetemaa-penned Eesti Televisiooncomedy television film Püha Susanna ehk meistrite kool, Constable Tults in the 1995 ETV historical drama miniseries Wikmani poisid, Hardi Tiidus in the Jaak Kilmi-directed 2005 ETV comedy-fantasy television filmKohtumine tundmatuga, and as Hendrik Soopalu in the Kanal 2 crime series Kelgukoerad in 2012. In 2013, he joined the cast of the Kanal 2 comedy seriesNaabriplika as the character Insener. In 2017 he joined the cast of the ETV ten-part drama seriesPank, which follows the rise and subsequent misfortunes of a new bank that which emerges in Estonia in the 1990s. Kalju Orro has also worked extensively as a voice actor and radio performer. In 1999, he was awarded the Estonian Radio Actor's Prize.
In addition to acting, Orro has written, compiled, and contributed to a number of published books on the history of Estonian theatre, including the two-volume Lavakooliraamat. Vana album, a collection of photographs taken by Orro of people and events associated with Estonian theatre, was published in 2002.
Personal life
Kalju Orro was married to theatre scholar, editor, and critic Reet Neimar who died in 2008. Their son Oliver Orro, an architect, author, and professor, was born in 1982.