Tomoko Sasaki (佐々木 知子, Sasaki Tomoko) was born on March 2, 1955. She is a Japanese lawyer, politician, novelist, and former prosecutor.

In 1983, she became a prosecutor. From 1993 to 1996, she worked at the United Nations Asia and Far East Institute for the Prevention of Crime and the Treatment of Offenders.

In 1998, she was elected to the House of Councillors, which is a part of Japan's national legislature. She helped create the Stalker Regulation Law of 2000. She later served as the director of the Women's Affairs Division in the Liberal Democratic Party. She did not run for office in 2004 but continued to be a member of the Party Ethics Committee in the LDP. She is known for supporting the use of capital punishment within the party.

In 2004, she started her own law firm. In 2005, she became a professor of law at Teikyo University.

As a novelist

Sasaki has written some mystery novels using the pen name Rei Matsuki (松木 麗, Matsuki Rei). She won the Seishi Yokomizo Prize for her book Koibumi in 1992.