After arriving at Sixways at 10.15am and being greeted by Warriors Chairman Cecil Duckworth, the Prince of Wales began his day by joining a reception for dignitaries and guests of the Regiment.
He then moved to the main pitch to receive a Royal salute, present the new Colours, inspect the ranks and make a short speech.
During the speech, the Prince of Wales said: "The presentation of new Colours is a special and symbolic moment in the history of a Regiment.
"I feel enormously proud and privileged, as Colonel-in-Chief of the Mercian Regiment, to be able to share this special moment with you and to present the new Colours.
"The presentation of new Colours provides a unique opportunity for the Mercian Regiment to remember colleagues, to reminisce about shared times, to renew our oaths of service, to build upon what has already been achieved and to look forward together to what the future might bring.
"It is therefore with immense pleasure that I join you on this important occasion."
The visit was the second time in four years that Sixways has been given the royal seal of approval after the Princess Royal officially opened the stadium development in 2009.