Katherine Sebov (born January 5, 1999 in Toronto, Ontario, Canada) is a Canadian professional tennis player. She reached a career-high WTA singles ranking of No. 199 on January 14, 2019 and a career-high WTA doubles ranking of No. 476 on February 4, 2019.
In 2017, Sebov reached her first professional final at the ITF 60K in Granby but was defeated by Cristiana Ferrando. In 2018 at the ITF 25K in Toyota, she reached her second final, losing to Dejana Radanović in three sets. In 2018, she won her first professional title at the ITF 60K in Saguenay, defeating Quirine Lemoine in the final.