She wore a Jane Taylor hat, emerald drop earrings, and the gold Irish Guards Shamrock Brooch.
Middleton deviated from the St. Patrick's Day green tradition for the second time, wearing a brown coat and matching hat in 2015.
Her outfit was praised by the public and fans.
Middleton's Gianvito Rossi pumps were an affordable option at $775.
The troops appreciated the couple's appearance at the event.