Margaret Elaine di Menna ONZM (8 July 1923 – 24 March 2014) was a New Zealand microbiologist. In 1954 she became the first woman to gain a Doctor of Philosophy degree from a New Zealand university. Her doctoral thesis at the University of Otago was entitled Yeasts of the human body, their nature and relationship.^[1] She had previously graduated with a MSc(Hons) from the same institution in 1948.^[2]

In 1990, di Menna was awarded the New Zealand 1990 Commemoration Medal,^[3] and in the 1997 New Year Honours, she was appointed an Officer of the New Zealand Order of Merit, for services to microbiology.^[4] In 2011, the reading room at Abbey College at the University of Otago was named in her honour.^[5] She was a prominent member of Zonta International.^[6]

She died in Hamilton in 2014.^[7]