Myrtle Sappo is a character from E. C. Segar's comic strip Sappo. She was originally one of the major characters in the strip, with the task of acting as foil to and dominating her much-smaller husband John, often with the aid of a rolling pin. After Professor Wotasnozzle was introduced, however, his science-based antics together with Sappo began to dominate the strip and Mrs. Sappo's role was reduced until she was no longer seen. She did not appear in the comic as produced by Bud Sagendorf and later authors, until she made her return in the "Sappo and Wotasnozzle and Myrtle" backup from IDW Publishing's Popeye comic book series.
- Myrtle Sappo was named after Segar's own wife, Myrtle Johnson Segar.