The modest Sister Ethel Normoyle, who has dedicated herself for the last seven years to helping the poor in a shanty town in South Africa, said she was "delighted" to be mentioned in the monarch's Christmas message.
But she said: "I don't think I would want any symbolism to Mother Teresa. We have just both shared in the theme of the poverty of people. We are just trying to do what everybody here is doing - to reach out to people who are broken and repressed. I'm just trying to do my bit to bring the compassion of Christ to people.
"The more you are involved in their lives, you become very aware of the poverty and suffering."
The modest 50-year-old nun, from Liscasey, County Clare, in the west of the Irish Republic, met the Queen when she visited South Africa in March.
The Queen used the historic occasion to see the work of the Little Company of Mary, in Missionvale, near Port Elizabeth, where Sister Ethel and her colleagues give hope and support to thousands of people living in horrendous poverty.
Sister Ethel described her feelings on the sunny day the Queen and her entourage called at Missionvale's school and clinic, built from humble beginnings seven years ago, and then looking its very best.
"She was really wonderful, interested and caring." Sister Ethel also praised the Princess of Wales's campaigning for disadvantaged groups in Britain.
"I have great admiration for her - she's really caring and has great compassion.