The attack killed eight people and injured four dozen more. All three suspects were killed by police.
Harry spent 45 minutes visiting various shop owners at Borough Market, including bakers and produce sellers. Harry, the fifth-in-line to the British throne, stopped to taste some chorizo from one stall inside the gourmet food marketplace and purchased doughnuts from one of the shopkeepers.
He also met with a security guard who was present on the night of the attack and stopped to meet restaurant staff near where the attackers were finally killed by police.
"Prince Harry was keen to come down as soon as possible to spread the message that this vibrant market is open for business," said a Kensington Palace spokesman.
Vendor Paul Wheeler told Harry he and others were baking extra bread for victims of the high-rise fire at Grenfell Tower that killed at least 17 people and injured nearly 80 in the residential building in North Kensington.
Wheeler told British newspapers that is was their turn to help victims.
"What happened here last week was tragic. What happened over there yesterday was unthinkable," Wheeler said.
"The tragedy at Grenfell Tower has left a number of local people in need of urgent assistance. The Duke and Duchess of Cambridge and Prince Harry are pleased the Evening Standard's Dispossessed Fund has immediately swung into action. As residents of the local area they are keen to offer their immediate support," their joint statement said.
Numerous individuals and businesses have donated nearly $1 million to the fund to help those displaced by the tragic fire.
Londoners have been donating food blankets and other items to many families who were left with nothing but the clothes on their backs. A makeshift shelter has been set up near the high-rise for the families left homeless by the fire.