The royal spent time chatting to the excited youngsters and taking part in the group's activities before taking a break to enjoy a cupcake.
During her visit, mother-of-two Sophie was shown the commemorative badges the Brownies had received to mark Prince William and Kate Middleton's royal wedding and the birth of their son, Prince George.
Emblazoned with a Union Jack and a teddy bear wearing a crown, the badge reads 'HRH Prince George of Cambridge, 22 July 2013'.
For the engagement, which included arts and crafts, Sophie wore a black belted trench coat over jeans and black heeled boots.
On her coat collar, the 48-year-old proudly sported her gold Brownies badge, symbolizing that she is president of Girlguiding.
Sophie's outing comes just days after is was revealed that her daughter, Lady Louise Windsor, had undergone successful eye surgery.
As Louise was born prematurely via an emergency Caesarean section, the ten-year-old has suffered from exotropia — a condition that turns the eyes outwards.
Fortunately the charming young girl can now see normally, following the operation.
The Queen's granddaughter has never allowed her eye problem to hold her back though, learning how to ride on horseback and excelling at her junior school.
The next big decision for her parents will be deciding which secondary school Louise goes to, and in the long run, whether she plays a public role in the royal family.