She was born in the city of Moscow, RSFSR, USSR. Her father was Vladimir Illarionovich Tokman (1937-1976), a journalist, writer, founder and editor-in-chief of the magazine "Studenchesky Meridian" (1974-1976), secretary of the Kharkiv Regional Committee of the Komsomol for propaganda, an employee of the Central Committee of the VLKSM, a publicist, awarded the Order of Friendship of Peoples. He died of cancer when Katya was eight years old and her sister Viktoriya was twelve. Her mother is Valentina Yakovlevna Tokman (October 24, 1940 - September 7, 2020), Jewish, a philologist by education. From the age of 5, Yekaterina began appearing in children's television programs "ABVGDeyka". The debut of the aspiring actress in cinema was the leading role of the ninth-grader Tanya Kornilova in the family melodrama "The Leader" directed by Boris Durov, which was released on the country's screens in 1984. On the set of this film in Sochi she met her future husband, Aleksandr Strizhenov, who was also involved in one of the leading roles in this picture. She graduated from the directing faculty of the Moscow State Institute of Culture. She performed in the productions "Underground" and "Hamlet" at the Anton Chekhov Theater, as well as in productions of the State Theater of the Film Actor. In 1996-1998 she played the role of Mama in the children's TV show "Sesame Street". She also appeared repeatedly in television commercials. Since January 1997 she has been the host of the program "Good Morning" on "Channel One" (until 2002 called "ORT").

From 1997 to 2005 she hosted this program together with her husband, and since 2005 alone. In 1997 she appeared in the music videos "Everything Will Be as You Want" and "For Her Alone" by the singer and composer Aleksandr Shevchenko. In 2007 she graduated from the gestalt therapy department of the Institute of Practical Psychology and Psychoanalysis. From September 2008 to April 2009 she took part in the "Channel One" project "Ice Age-2", where her partner in ice dancing was the figure skater Aleksey Tikhonov. Her outfits are sewn mainly by her sister, the fashion designer Viktoriya Andreyanova, a graduate of the A.N. Kosygin Moscow State Textile University. From December 2010 to December 2011 she was the editor-in-chief of the magazine "ITALIA - Made in Italy". From September 6 to October 11, 2013 she hosted the talk show "For and Against" on "Channel One" together with Aleksandr Gordon. On September 29, 2013 she was one of the main hosts of the charity telethon "Vsem Miron", dedicated to helping those affected by the flood in the Far East. On November 25, 2013, "Channel One" launched a new television project about the relationship between a man and a woman, "They and We", whose hosts were Yekaterina Strizhenova and Aleksandr Gordon. From September 15, 2014 to the present she has hosted the political talk show "Time Will Tell" on "Channel One" together with Pyotr Tolstoy.