Along with Prince Harry, Meghan stopped off at One25 during a tour of the city.
The charity offers help and support to women looking to break free from prostitution.
Alongside talking to volunteers, the duchess wrote personal messages of love and empowerment on bananas destined for food parcels for the women.
Megan revealed she was inspired to leave positive messages in the food bags after learning about a similar gesture made for school children.
Some of the 150 women who are still street sex-working in Bristol received the parcels containing the actress-turned-royal's message later in the evening.
The duchess said: "I was thinking about this the other day. I saw this programme this woman had started in the States on a school lunch programme when on each of the bananas she wrote an affirmation or something to make the kids feel really empowered.
"I thought it was the most incredible idea - this small gesture."
Founded through a Christian vision, One25's says it tried to shape a culture and practice based on the example, teaching and values of Jesus. These values embrace unconditional love, acceptance, justice, inclusivity and a mutual respect for all.
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