Katerina Helmi (Athens, 12 August 1939 - Kifissia, 15 April 2023) was a Greek actress. She became widely known to the Greek audience through roles in some of the most beloved films of Greek cinema.

Her first appearance in cinema was in 1957 in the film Barbagiannis the Pitcher, but her greatest success is The Red Lights. She was also the rival of Aliki Vougiouklaki in the film Our Love. During her career, she has participated in more than 25 films and 4 television series.